--- a/dom/locales/en-US/chrome/netError.dtd
+++ b/dom/locales/en-US/chrome/netError.dtd
@@ -75,13 +75,13 @@
 ">
 
 <!ENTITY phishingBlocked.title "Suspected Web Forgery!">
 <!ENTITY phishingBlocked.longDesc "
 <p>Entering any personal information on this page may result in identity theft or other fraud.</p>
 <p>These types of web forgeries are used in scams known as phishing attacks, in which fraudulent web pages and emails are used to imitate sources you may trust.</p>
 ">
 
-<!ENTITY securityOverride.linkText "Or you can add an exception…">
-<!ENTITY securityOverride.warningText "
-<p>You should not add an exception if you are using an internet connection that you do not trust completely or if you are not used to seeing a warning for this server.</p>
-<p>If you still wish to add an exception for this site, you can do so in your advanced encryption settings.</p>
-">
+<!-- Include app-specific error messages - do not change this in localization!
+     Some applications might override netErrorApp.dtd with their specific version,
+     this inclusion needs to be intact for that approach to work correctly. -->
+<!ENTITY % netErrorAppDTD SYSTEM "chrome://global/locale/netErrorApp.dtd">
+%netErrorAppDTD;

new file mode 100644
--- /dev/null
+++ b/dom/locales/en-US/chrome/netErrorApp.dtd
@@ -0,0 +1,9 @@
+<!-- Error messages that are likely to be overridden by applications go in this
+     file, all messages that likely don't need to tie into app-specific UI
+     should go into netError.dtd -->
+
+<!ENTITY securityOverride.linkText "Or you can add an exception…">
+<!ENTITY securityOverride.warningText "
+<p>You should not add an exception if you are using an internet connection that you do not trust completely or if you are not used to seeing a warning for this server.</p>
+<p>If you still wish to add an exception for this site, you can do so in your advanced encryption settings.</p>
+">

--- a/dom/locales/jar.mn
+++ b/dom/locales/jar.mn
@@ -2,16 +2,17 @@
 
 @AB_CD@.jar:
   locale/@AB_CD@/global/css.properties                         (%chrome/layout/css.properties)
   locale/@AB_CD@/global/xbl.properties                         (%chrome/layout/xbl.properties)
   locale/@AB_CD@/global/xul.properties                         (%chrome/layout/xul.properties)
   locale/@AB_CD@/global/printing.properties                    (%chrome/layout/printing.properties)
   locale/@AB_CD@/global/layout_errors.properties               (%chrome/layout/layout_errors.properties)
   locale/@AB_CD@/global/netError.dtd                           (%chrome/netError.dtd)
+  locale/@AB_CD@/global/netErrorApp.dtd                        (%chrome/netErrorApp.dtd)
   locale/@AB_CD@/global/global.dtd                             (%chrome/global.dtd)
   locale/@AB_CD@/global/appstrings.properties                  (%chrome/appstrings.properties)
   locale/@AB_CD@/global/charsetTitles.properties               (%chrome/charsetTitles.properties)
   locale/@AB_CD@/global/global-strres.properties               (%chrome/global-strres.properties)
   locale/@AB_CD@/global/plugins.properties                     (%chrome/plugins.properties)
   locale/@AB_CD@/global/nsWebBrowserPersist.properties         (%chrome/nsWebBrowserPersist.properties)
   locale/@AB_CD@/global/printdialog.properties                 (%chrome/printdialog.properties)
   locale/@AB_CD@/global/xslt/xslt.properties                   (%chrome/xslt/xslt.properties)