--- a/netwerk/base/public/Makefile.in
+++ b/netwerk/base/public/Makefile.in
@@ -99,17 +99,16 @@ XPIDLSRCS	= \
 		nsIServerSocket.idl \
 		nsIResumableChannel.idl \
 		nsIRequestObserverProxy.idl \
 		nsIStreamListenerTee.idl \
 		nsISimpleStreamListener.idl \
 		nsIStreamTransportService.idl \
 		nsIStreamLoader.idl \
 		nsISyncStreamListener.idl \
-		nsISystemProxySettings.idl \
 		nsIUnicharStreamLoader.idl \
 		nsIStandardURL.idl \
 		nsINestedURI.idl \
 		nsIURLParser.idl \
 		nsIURIChecker.idl \
 		nsISecurityEventSink.idl \
 		nsISecretDecoderRing.idl \
 		nsISecureBrowserUI.idl \

--- a/netwerk/base/src/nsPACMan.h
+++ b/netwerk/base/src/nsPACMan.h
@@ -123,24 +123,16 @@ public:
    */
   nsresult LoadPACFromURI(nsIURI *pacURI);
 
   /**
    * Returns true if we are currently loading the PAC file.
    */
   PRBool IsLoading() { return mLoader != nsnull; }
 
-  /**
-   * Returns true if the given URI matches the URI of our PAC file.
-   */
-  PRBool IsPACURI(nsIURI *uri) {
-    PRBool result;
-    return mPACURI && NS_SUCCEEDED(mPACURI->Equals(uri, &result)) && result;
-  }
-
 private:
   NS_DECL_NSISTREAMLOADEROBSERVER
   NS_DECL_NSIINTERFACEREQUESTOR
   NS_DECL_NSICHANNELEVENTSINK
 
   ~nsPACMan();
 
   /**
@@ -165,16 +157,24 @@ private:
    */
   void MaybeReloadPAC();
 
   /**
    * Called when we fail to load the PAC file.
    */
   void OnLoadFailure();
 
+  /**
+   * Returns true if the given URI matches the URI of our PAC file.
+   */
+  PRBool IsPACURI(nsIURI *uri) {
+    PRBool result;
+    return mPACURI && NS_SUCCEEDED(mPACURI->Equals(uri, &result)) && result;
+  }
+
 private:
   nsCOMPtr<nsIProxyAutoConfig> mPAC;
   nsCOMPtr<nsIURI>             mPACURI;
   PRCList                      mPendingQ;
   nsCOMPtr<nsIStreamLoader>    mLoader;
   PRPackedBool                 mLoadPending;
   PRPackedBool                 mShutdown;
   PRTime                       mScheduledReload;

--- a/netwerk/base/src/nsProtocolProxyService.cpp
+++ b/netwerk/base/src/nsProtocolProxyService.cpp
@@ -399,22 +399,16 @@ nsProtocolProxyService::PrefsChanged(nsI
                     prefBranch->SetIntPref(PROXY_PREF("type"), type);
             } else if (type >= eProxyConfig_Last) {
                 LOG(("unknown proxy type: %lu; assuming direct\n", type));
                 type = eProxyConfig_Direct;
             }
             mProxyConfig = static_cast<ProxyConfig>(type);
             reloadPAC = PR_TRUE;
         }
-
-        if (mProxyConfig == eProxyConfig_System) {
-            mSystemProxySettings = do_GetService(NS_SYSTEMPROXYSETTINGS_CONTRACTID);
-        } else {
-            mSystemProxySettings = nsnull;
-        }
     }
 
     if (!pref || !strcmp(pref, PROXY_PREF("http")))
         proxy_GetStringPref(prefBranch, PROXY_PREF("http"), mHTTPProxyHost);
 
     if (!pref || !strcmp(pref, PROXY_PREF("http_port")))
         proxy_GetIntPref(prefBranch, PROXY_PREF("http_port"), mHTTPProxyPort);
 
@@ -462,48 +456,43 @@ nsProtocolProxyService::PrefsChanged(nsI
 
     if (!pref || !strcmp(pref, PROXY_PREF("no_proxies_on"))) {
         rv = prefBranch->GetCharPref(PROXY_PREF("no_proxies_on"),
                                      getter_Copies(tempString));
         if (NS_SUCCEEDED(rv))
             LoadHostFilters(tempString.get());
     }
 
-    // We're done if not using something that could give us a PAC URL
-    // (PAC, WPAD or System)
-    if (mProxyConfig != eProxyConfig_PAC && mProxyConfig != eProxyConfig_WPAD &&
-        mProxyConfig != eProxyConfig_System)
+    // We're done if not using PAC or WPAD
+    if (mProxyConfig != eProxyConfig_PAC && mProxyConfig != eProxyConfig_WPAD)
         return;
 
     // OK, we need to reload the PAC file if:
     //  1) network.proxy.type changed, or
     //  2) network.proxy.autoconfig_url changed and PAC is configured
 
     if (!pref || !strcmp(pref, PROXY_PREF("autoconfig_url")))
         reloadPAC = PR_TRUE;
 
     if (reloadPAC) {
         tempString.Truncate();
         if (mProxyConfig == eProxyConfig_PAC) {
             prefBranch->GetCharPref(PROXY_PREF("autoconfig_url"),
                                     getter_Copies(tempString));
-        } else {
+        }
+        else if (mProxyConfig == eProxyConfig_WPAD) {
             // We diverge from the WPAD spec here in that we don't walk the
             // hosts's FQDN, stripping components until we hit a TLD.  Doing so
             // is dangerous in the face of an incomplete list of TLDs, and TLDs
             // get added over time.  We could consider doing only a single
             // substitution of the first component, if that proves to help
             // compatibility.
-            if (mSystemProxySettings)
-                mSystemProxySettings->GetPACURI(tempString);
-            else
-                tempString.AssignLiteral(WPAD_URL);
+            tempString.AssignLiteral(WPAD_URL);
         }
-        if (!tempString.IsEmpty())
-            ConfigureFromPAC(tempString);
+        ConfigureFromPAC(tempString);
     }
 }
 
 PRBool
 nsProtocolProxyService::CanUseProxy(nsIURI *aURI, PRInt32 defaultPort) 
 {
     if (mHostFiltersArray.Count() == 0)
         return PR_TRUE;
@@ -761,26 +750,23 @@ nsresult
 nsProtocolProxyService::ConfigureFromPAC(const nsCString &spec)
 {
     if (!mPACMan) {
         mPACMan = new nsPACMan();
         if (!mPACMan)
             return NS_ERROR_OUT_OF_MEMORY;
     }
 
+    mFailedProxies.Clear();
+
     nsCOMPtr<nsIURI> pacURI;
     nsresult rv = NS_NewURI(getter_AddRefs(pacURI), spec);
     if (NS_FAILED(rv))
         return rv;
 
-    if (mPACMan->IsPACURI(pacURI))
-        return NS_OK;
-
-    mFailedProxies.Clear();
-
     return mPACMan->LoadPACFromURI(pacURI);
 }
 
 void
 nsProtocolProxyService::ProcessPACString(const nsCString &pacString,
                                          nsIProxyInfo **result)
 {
     if (pacString.IsEmpty()) {
@@ -945,20 +931,18 @@ nsProtocolProxyService::NewProxyInfo(con
 }
 
 NS_IMETHODIMP
 nsProtocolProxyService::GetFailoverForProxy(nsIProxyInfo  *aProxy,
                                             nsIURI        *aURI,
                                             nsresult       aStatus,
                                             nsIProxyInfo **aResult)
 {
-    // We only support failover when a PAC file is configured, either
-    // directly or via system settings
-    if (mProxyConfig != eProxyConfig_PAC && mProxyConfig != eProxyConfig_WPAD &&
-        mProxyConfig != eProxyConfig_System)
+    // We only support failover when a PAC file is configured.
+    if (mProxyConfig != eProxyConfig_PAC && mProxyConfig != eProxyConfig_WPAD)
         return NS_ERROR_NOT_AVAILABLE;
 
     // Verify that |aProxy| is one of our nsProxyInfo objects.
     nsCOMPtr<nsProxyInfo> pi = do_QueryInterface(aProxy);
     NS_ENSURE_ARG(pi);
     // OK, the QI checked out.  We can proceed.
 
     // Remember that this proxy is down.
@@ -1245,47 +1229,25 @@ nsProtocolProxyService::Resolve_Internal
     NS_ENSURE_ARG_POINTER(uri);
 
     *usePAC = PR_FALSE;
     *result = nsnull;
 
     if (!(info.flags & nsIProtocolHandler::ALLOWS_PROXY))
         return NS_OK;  // Can't proxy this (filters may not override)
 
-    if (mSystemProxySettings) {
-        nsCAutoString PACURI;
-        if (NS_SUCCEEDED(mSystemProxySettings->GetPACURI(PACURI)) &&
-            !PACURI.IsEmpty()) {
-            // Switch to new PAC file if that setting has changed. If the setting
-            // hasn't changed, ConfigureFromPAC will exit early.
-            nsresult rv = ConfigureFromPAC(PACURI);
-            if (NS_FAILED(rv))
-                return rv;
-        } else {
-            nsCAutoString proxy;
-            nsresult rv = mSystemProxySettings->GetProxyForURI(uri, proxy);
-            if (NS_SUCCEEDED(rv)) {
-                ProcessPACString(proxy, result);
-                return NS_OK;
-            }
-            // no proxy, stop search
-            return NS_OK;
-        }
-    }
-
     // if proxies are enabled and this host:port combo is supposed to use a
     // proxy, check for a proxy.
     if (mProxyConfig == eProxyConfig_Direct ||
             (mProxyConfig == eProxyConfig_Manual &&
              !CanUseProxy(uri, info.defaultPort)))
         return NS_OK;
-
+    
     // Proxy auto config magic...
-    if (mProxyConfig == eProxyConfig_PAC || mProxyConfig == eProxyConfig_WPAD ||
-        mProxyConfig == eProxyConfig_System) {
+    if (mProxyConfig == eProxyConfig_PAC || mProxyConfig == eProxyConfig_WPAD) {
         // Do not query PAC now.
         *usePAC = PR_TRUE;
         return NS_OK;
     }
 
     // proxy info values
     const char *type = nsnull;
     const nsACString *host = nsnull;

--- a/netwerk/base/src/nsProtocolProxyService.h
+++ b/netwerk/base/src/nsProtocolProxyService.h
@@ -42,17 +42,16 @@
 #include "nsString.h"
 #include "nsCOMPtr.h"
 #include "nsAutoPtr.h"
 #include "nsVoidArray.h"
 #include "nsIPrefBranch.h"
 #include "nsIProtocolProxyService2.h"
 #include "nsIProtocolProxyFilter.h"
 #include "nsIProxyAutoConfig.h"
-#include "nsISystemProxySettings.h"
 #include "nsIProxyInfo.h"
 #include "nsIObserver.h"
 #include "nsDataHashtable.h"
 #include "nsHashKeys.h"
 #include "nsPACMan.h"
 #include "prtime.h"
 #include "prmem.h"
 #include "prio.h"
@@ -311,17 +310,16 @@ public:
 protected:
 
     enum ProxyConfig {
         eProxyConfig_Direct,
         eProxyConfig_Manual,
         eProxyConfig_PAC,
         eProxyConfig_Direct4x,
         eProxyConfig_WPAD,
-        eProxyConfig_System, // use system proxy settings if available, otherwise DIRECT
         eProxyConfig_Last
     };
 
     // simplified array of filters defined by this struct
     struct HostInfo {
         PRBool  is_ipaddr;
         PRInt32 port;
         union {
@@ -373,16 +371,15 @@ protected:
     PRInt32                      mHTTPSProxyPort;
     
     nsCString                    mSOCKSProxyHost;
     PRInt32                      mSOCKSProxyPort;
     PRInt32                      mSOCKSProxyVersion;
     PRBool                       mSOCKSProxyRemoteDNS;
 
     nsRefPtr<nsPACMan>           mPACMan;  // non-null if we are using PAC
-    nsCOMPtr<nsISystemProxySettings> mSystemProxySettings;
 
     PRTime                       mSessionStart;
     nsFailedProxyTable           mFailedProxies;
     PRInt32                      mFailedProxyTimeout;
 };
 
 #endif // !nsProtocolProxyService_h__

--- a/netwerk/build/nsNetCID.h
+++ b/netwerk/build/nsNetCID.h
@@ -321,20 +321,16 @@
     0x11b2,                                          \
     {0xa9, 0x04, 0xac, 0x1d, 0x6d, 0xa7, 0x7a, 0x02} \
 }
 
 // component implementing nsIIncrementalDownload.
 #define NS_INCREMENTALDOWNLOAD_CONTRACTID \
     "@mozilla.org/network/incremental-download;1"
 
-// component implementing nsISystemProxySettings.
-#define NS_SYSTEMPROXYSETTINGS_CONTRACTID \
-    "@mozilla.org/system-proxy-settings;1"
-
 // service implementing nsIStreamTransportService
 #define NS_STREAMTRANSPORTSERVICE_CLASSNAME \
     "nsStreamTransportService"
 #define NS_STREAMTRANSPORTSERVICE_CONTRACTID \
     "@mozilla.org/network/stream-transport-service;1"
 #define NS_STREAMTRANSPORTSERVICE_CID \
 { /* 0885d4f8-f7b8-4cda-902e-94ba38bc256e */         \
     0x0885d4f8,                                      \

--- a/toolkit/Makefile.in
+++ b/toolkit/Makefile.in
@@ -46,20 +46,16 @@ include $(DEPTH)/config/autoconf.mk
 DIRS	= \
 		content \
 		locales \
 		obsolete \
 		profile \
 		themes \
 		$(NULL)
 
-ifneq (,$(filter gtk2,$(MOZ_WIDGET_TOOLKIT)))
-DIRS += system/unixproxy
-endif
-
 ifdef MOZ_CRASHREPORTER
 DIRS += crashreporter
 endif
 
 ifndef MINIMO
 DIRS += \
 	xre \
         mozapps \

--- a/toolkit/library/libxul-config.mk
+++ b/toolkit/library/libxul-config.mk
@@ -142,24 +142,16 @@ endif
 ifdef MOZ_XPFE_COMPONENTS
 DEFINES += -DMOZ_XPFE_COMPONENTS
 COMPONENT_LIBS += \
 	mozfind \
 	appcomps \
 	$(NULL)
 endif
 
-ifdef MOZ_XUL
-ifdef MOZ_ENABLE_GTK2
-COMPONENT_LIBS += \
-        unixproxy \
-        $(NULL)
-endif
-endif
-
 ifdef MOZ_PERF_METRICS
 EXTRA_DSO_LIBS  += mozutil_s
 endif
 
 ifdef MOZ_XPINSTALL
 DEFINES += -DMOZ_XPINSTALL
 COMPONENT_LIBS += \
 	xpinstall \

--- a/toolkit/library/nsStaticXULComponents.cpp
+++ b/toolkit/library/nsStaticXULComponents.cpp
@@ -257,25 +257,16 @@
 #endif
 
 #ifdef MOZ_XMLEXTRAS
 #define XMLEXTRAS_MODULE MODULE(nsXMLExtrasModule)
 #else
 #define XMLEXTRAS_MODULE
 #endif
 
-#ifdef MOZ_XUL
-#ifdef MOZ_ENABLE_GTK2
-#define UNIXPROXY_MODULE MODULE(nsUnixProxyModule)
-#endif
-#endif
-#ifndef UNIXPROXY_MODULE
-#define UNIXPROXY_MODULE
-#endif
-
 #define XUL_MODULES                          \
     MODULE(xpconnect)                        \
     MATHML_MODULES                           \
     MODULE(nsUConvModule)                    \
     MODULE(nsI18nModule)                     \
     MODULE(nsChardetModule)                  \
     UNIVERSALCHARDET_MODULE                  \
     MODULE(necko)                            \
@@ -317,17 +308,16 @@
     XPINSTALL_MODULES                        \
     JSDEBUGGER_MODULES                       \
     MODULE(BOOT)                             \
     MODULE(NSS)                              \
     SYSTEMPREF_MODULES                       \
     SPELLCHECK_MODULE                        \
     XMLEXTRAS_MODULE                         \
     LAYOUT_DEBUG_MODULE                      \
-    UNIXPROXY_MODULE                         \
     /* end of list */
 
 #define MODULE(_name) \
 NSGETMODULE_ENTRY_POINT(_name) (nsIComponentManager*, nsIFile*, nsIModule**);
 
 XUL_MODULES
 
 #undef MODULE

--- a/toolkit/system/gnome/nsGConfService.cpp
+++ b/toolkit/system/gnome/nsGConfService.cpp
@@ -33,20 +33,16 @@
  * and other provisions required by the GPL or the LGPL. If you do not delete
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #include "nsGConfService.h"
 #include "nsStringAPI.h"
-#include "nsCOMPtr.h"
-#include "nsComponentManagerUtils.h"
-#include "nsISupportsPrimitives.h"
-#include "nsIMutableArray.h"
 
 #include <gconf/gconf-client.h>
 
 nsGConfService::~nsGConfService()
 {
   if (mClient)
     g_object_unref(mClient);
 }
@@ -123,47 +119,16 @@ nsGConfService::GetFloat(const nsACStrin
     g_error_free(error);
     return NS_ERROR_FAILURE;
   }
 
   return NS_OK;
 }
 
 NS_IMETHODIMP
-nsGConfService::GetStringList(const nsACString &aKey, nsIArray** aResult)
-{
-  nsCOMPtr<nsIMutableArray> items(do_CreateInstance(NS_ARRAY_CONTRACTID));
-  if (!items)
-    return NS_ERROR_OUT_OF_MEMORY;
-    
-  GError* error = nsnull;
-  GSList* list = gconf_client_get_list(mClient, PromiseFlatCString(aKey).get(),
-                                       GCONF_VALUE_STRING, &error);
-  if (error) {
-    g_error_free(error);
-    return NS_ERROR_FAILURE;
-  }
-
-  for (GSList* l = list; l; l = l->next) {
-    nsCOMPtr<nsISupportsString> obj(do_CreateInstance(NS_SUPPORTS_CSTRING_CONTRACTID));
-    if (!obj) {
-      g_slist_free(list);
-      return NS_ERROR_OUT_OF_MEMORY;
-    }
-    obj->SetData(NS_ConvertUTF8toUTF16((const char*)l->data));
-    items->AppendElement(obj, PR_FALSE);
-    g_free(l->data);
-  }
-  
-  g_slist_free(list);
-  NS_ADDREF(*aResult = items);
-  return NS_OK;
-}
-
-NS_IMETHODIMP
 nsGConfService::SetBool(const nsACString &aKey, PRBool aValue)
 {
   PRBool res = gconf_client_set_bool(mClient, PromiseFlatCString(aKey).get(),
                                      aValue, nsnull);
 
   return res ? NS_OK : NS_ERROR_FAILURE;
 }
 

--- a/toolkit/toolkit-makefiles.sh
+++ b/toolkit/toolkit-makefiles.sh
@@ -656,17 +656,16 @@ MAKEFILES_xulapp="
   toolkit/components/commandlines/src/Makefile
   toolkit/components/console/Makefile
   toolkit/components/cookie/Makefile
   toolkit/components/downloads/public/Makefile
   toolkit/components/downloads/Makefile
   toolkit/components/downloads/src/Makefile
   toolkit/components/filepicker/Makefile
   toolkit/system/gnome/Makefile
-  toolkit/system/unixproxy/Makefile
   toolkit/components/help/Makefile
   toolkit/components/history/Makefile
   toolkit/components/history/public/Makefile
   toolkit/components/history/src/Makefile
   toolkit/components/passwordmgr/Makefile
   toolkit/components/passwordmgr/public/Makefile
   toolkit/components/passwordmgr/src/Makefile
   toolkit/components/passwordmgr/content/Makefile

--- a/xpcom/system/nsIGConfService.idl
+++ b/xpcom/system/nsIGConfService.idl
@@ -32,33 +32,26 @@
  * decision by deleting the provisions above and replace them with the notice
  * and other provisions required by the GPL or the LGPL. If you do not delete
  * the provisions above, a recipient may use your version of this file under
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
 
 #include "nsISupports.idl"
-#include "nsIArray.idl"
 
-[scriptable, uuid(5009acae-6973-48c3-b6d6-52c692cc5d9d)]
+[scriptable, uuid(01ac7b2e-c07c-465f-b35c-542eaef420a9)]
 interface nsIGConfService : nsISupports
 {
   /* Basic registry access */
   boolean       getBool(in AUTF8String key);
   AUTF8String   getString(in AUTF8String key);
   long          getInt(in AUTF8String key);
   float         getFloat(in AUTF8String key);
 
-  /*
-   * Use this to return any list items in GConf, this will return
-   * an array of UTF16 nsISupportsString's.
-   */
-  nsIArray      getStringList(in AUTF8String key);
-
   void setBool(in AUTF8String key, in boolean value);
   void setString(in AUTF8String key, in AUTF8String value);
   void setInt(in AUTF8String key, in long value);
   void setFloat(in AUTF8String key, in float value);
 
   /*
    * Look up the handler for a protocol under the
    * /desktop/gnome/url-handlers hierarchy.