diff --git a/mozilla/docshell/base/appstrings.properties b/mozilla/docshell/base/appstrings.properties
index bf1fed3c425..9a84fb2f940 100644
--- a/mozilla/docshell/base/appstrings.properties
+++ b/mozilla/docshell/base/appstrings.properties
@@ -27,3 +27,4 @@ redirectLoop=Redirection limit for this URL exceeded.  Loading aborted.
 repost=The page you are trying to view contains POSTDATA that has expired from cache. If you resend the data, any action the form carried out (such as a search or online purchase) will be repeated. To resend the data, click OK. Otherwise, click Cancel.
 repostConfirm=The page you are trying to view contains POSTDATA. If you resend the data, any action the form carried out (such as a search or online purchase) will be repeated. To resend the data, click OK. Otherwise, click Cancel.
 fileNotFound=%s does not exist or could not be accessed. Please check the file path and try again.
+unknownSocketType=Unknown socket type.  Loading aborted.
diff --git a/mozilla/docshell/base/nsWebShell.cpp b/mozilla/docshell/base/nsWebShell.cpp
index 840dd082d1c..5a52fd3abb1 100644
--- a/mozilla/docshell/base/nsWebShell.cpp
+++ b/mozilla/docshell/base/nsWebShell.cpp
@@ -63,6 +63,7 @@ typedef unsigned long HMTX;
 #include "nsNetUtil.h"
 #include "nsIProtocolHandler.h"
 #include "nsIDNSService.h"
+#include "nsISocketProvider.h"
 #include "nsIRefreshURI.h"
 #include "nsIScriptGlobalObject.h"
 #include "nsIScriptGlobalObjectOwner.h"
@@ -1236,6 +1237,23 @@ nsresult nsWebShell::EndPageLoad(nsIWebProgress *aProgress,
                                            getter_Copies(messageStr));
       if (NS_FAILED(rv)) return rv;
 
+      prompter->Alert(nsnull, messageStr);
+    }
+    else if (aStatus == NS_ERROR_UNKNOWN_SOCKET_TYPE) {
+      nsCOMPtr<nsIPrompt> prompter;
+      nsCOMPtr<nsIStringBundle> stringBundle;
+
+      rv = GetPromptAndStringBundle(getter_AddRefs(prompter),
+                                    getter_AddRefs(stringBundle));
+      if (!stringBundle) {
+        return rv;
+      }
+
+      nsXPIDLString messageStr;
+      rv = stringBundle->GetStringFromName(NS_LITERAL_STRING("unknownSocketType").get(),
+                                           getter_Copies(messageStr));
+      if (NS_FAILED(rv)) return rv;
+
       prompter->Alert(nsnull, messageStr);
     }
   } // if we have a host