--- a/mailnews/base/util/nsMsgProtocol.cpp
+++ b/mailnews/base/util/nsMsgProtocol.cpp
@@ -73,16 +73,20 @@ nsresult nsMsgProtocol::InitFromURI(nsIU
   nsCOMPtr <nsIMsgMailNewsUrl> mailUrl = do_QueryInterface(aUrl);
   if (mailUrl)
   {
     mailUrl->GetLoadGroup(getter_AddRefs(m_loadGroup));
     nsCOMPtr<nsIMsgStatusFeedback> statusFeedback;
     mailUrl->GetStatusFeedback(getter_AddRefs(statusFeedback));
     mProgressEventSink = do_QueryInterface(statusFeedback);
   }
+
+  // Reset channel data in case the object is reused and initialised again.
+  mCharset.Truncate();
+
   return NS_OK;
 }
 
 nsMsgProtocol::~nsMsgProtocol()
 {}
 
 
 static bool gGotTimeoutPref;