diff --git a/mozilla/security/manager/pki/resources/content/pref-ssl.xul b/mozilla/security/manager/pki/resources/content/pref-ssl.xul
index 7371eb4b4d4..5cafc758db0 100644
--- a/mozilla/security/manager/pki/resources/content/pref-ssl.xul
+++ b/mozilla/security/manager/pki/resources/content/pref-ssl.xul
@@ -36,7 +36,8 @@
   <script language="JavaScript">
   <![CDATA[
     _elementIDs = ["enableSSL2", "enableSSL3", "enableTLS", 
-        "warnEnteringSecure", "warnInsecurePost", "warnInsecurePostFromSecure",
+        "warnEnteringSecure", "warnEnteringWeak", 
+        "warnInsecurePost", "warnInsecurePostFromSecure",
         "warnSecureRedirect", "warnSecureRedirectToInsecure",
         "warnViewMixed", "certSelection" ];
   ]]>
@@ -81,6 +82,10 @@ Set Netscape to show a warning and ask permission before:
       label="Entering a site that supports encryption"
               pref="true" preftype="bool" prefstring="security.warn_entering_secure"
               prefattribute="checked"/>
+    <checkbox id="warnEnteringWeak" 
+		  value="Entering a site that uses weak encryption"
+              pref="true" preftype="bool" prefstring="security.warn_entering_weak"
+              prefattribute="checked"/>
     <checkbox id="warnInsecurePost"
       label="Sending form data from an insecure page to an insecure page"
               pref="true" preftype="bool" prefstring="security.warn_submit_insecure"
diff --git a/mozilla/security/manager/pki/src/nsNSSDialogs.cpp b/mozilla/security/manager/pki/src/nsNSSDialogs.cpp
index c765ca543ac..50ad9bbaa2a 100644
--- a/mozilla/security/manager/pki/src/nsNSSDialogs.cpp
+++ b/mozilla/security/manager/pki/src/nsNSSDialogs.cpp
@@ -55,6 +55,7 @@
 #define STRING_BUNDLE_URL    "chrome://communicator/locale/security.properties"
 
 #define ENTER_SITE_PREF      "security.warn_entering_secure"
+#define WEAK_SITE_PREF       "security.warn_entering_weak"
 #define LEAVE_SITE_PREF      "security.warn_leaving_secure"
 #define MIXEDCONTENT_PREF    "security.warn_viewing_mixed"
 #define INSECURE_SUBMIT_PREF "security.warn_submit_insecure"
@@ -499,6 +500,16 @@ nsNSSDialogs::AlertEnteringSecure(nsIInterfaceRequestor *ctx)
   return rv;
 }
 
+nsresult
+nsNSSDialogs::AlertEnteringWeak(nsIInterfaceRequestor *ctx)
+{
+  nsresult rv;
+
+  rv = AlertDialog(ctx, WEAK_SITE_PREF,
+                   NS_LITERAL_STRING("WeakSiteMessage").get());
+
+  return rv;
+}
 
 nsresult
 nsNSSDialogs::AlertLeavingSecure(nsIInterfaceRequestor *ctx)
diff --git a/mozilla/security/manager/ssl/public/nsINSSDialogs.idl b/mozilla/security/manager/ssl/public/nsINSSDialogs.idl
index 4923617fff6..c75b4e2b348 100644
--- a/mozilla/security/manager/ssl/public/nsINSSDialogs.idl
+++ b/mozilla/security/manager/ssl/public/nsINSSDialogs.idl
@@ -78,6 +78,11 @@ interface nsISecurityWarningDialogs : nsISupports
    */
   void alertEnteringSecure(in nsIInterfaceRequestor ctx);
 
+  /**
+   * alertEnteringWeak
+   */
+  void alertEnteringWeak(in nsIInterfaceRequestor ctx);
+
   /**
    * alertLeavingSecure
    */
diff --git a/mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp b/mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp
index f60fc8a7940..bd05997a221 100644
--- a/mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp
+++ b/mozilla/security/manager/ssl/src/nsNSSCallbacks.cpp
@@ -118,15 +118,20 @@ void HandshakeCallback(PRFileDesc* fd, void* client_data) {
   PRInt32 sslStatus;
   char* signer = nsnull;
   nsresult rv;
+  PRInt32 encryptBits;
 
   if (SECSuccess == SSL_SecurityStatus(fd, &sslStatus, nsnull, nsnull,
-                                       nsnull, &signer, nsnull))
+                                       &encryptBits, &signer, nsnull))
     {
       PRInt32 secStatus;
       if (sslStatus == SSL_SECURITY_STATUS_OFF)
         secStatus = nsIWebProgressListener::STATE_IS_BROKEN;
+      else if (encryptBits >= 90)
+        secStatus = (nsIWebProgressListener::STATE_IS_SECURE |
+                     nsIWebProgressListener::STATE_SECURE_HIGH);
       else
-        secStatus = nsIWebProgressListener::STATE_IS_SECURE;
+        secStatus = (nsIWebProgressListener::STATE_IS_SECURE |
+                     nsIWebProgressListener::STATE_SECURE_LOW);
 
       CERTName* certName = CERT_AsciiToName(signer);
       char* caName = CERT_GetOrgName(certName);
diff --git a/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.cpp b/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.cpp
index c3814abd963..727f44795d6 100644
--- a/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.cpp
+++ b/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.cpp
@@ -66,6 +66,8 @@
 
 static NS_DEFINE_CID(kCStringBundleServiceCID,  NS_STRINGBUNDLESERVICE_CID);
 
+#define IS_SECURE(state) ((state & 0xFFFF) == STATE_IS_SECURE)
+
 #if defined(PR_LOGGING)
 //
 // Log module for nsSecureBroswerUI logging...
@@ -189,7 +191,7 @@ static nsresult IsChildOfDomWindow(nsIDOMWindow *parent, nsIDOMWindow *child,
   return NS_OK;
 }
 
-static PRInt16 GetSecurityStateFromChannel(nsIChannel* aChannel)
+static PRInt32 GetSecurityStateFromChannel(nsIChannel* aChannel)
 {
   nsresult res;
   PRInt32 securityState;
@@ -313,23 +315,29 @@ nsSecureBrowserUIImpl::OnStateChange(nsIWebProgress* aWebProgress,
   // A document has finished loading
   if ((aProgressStateFlags & STATE_STOP) &&
       (aProgressStateFlags & STATE_IS_NETWORK) &&
-      (mSecurityState == STATE_IS_SECURE ||
+      (IS_SECURE(mSecurityState) ||
        mSecurityState == STATE_IS_BROKEN))
     {
-      if (mSecurityState == STATE_IS_SECURE) {
+      if (IS_SECURE(mSecurityState)) {
         // XXX Shouldn't we do this even if the state is broken?
         // XXX Shouldn't we grab the pickled status at STATE_NET_TRANSFERRING?
         
-        if (GetSecurityStateFromChannel(channel) == STATE_IS_SECURE) {
+        if (IS_SECURE(GetSecurityStateFromChannel(channel))) {
           // Everything looks okay.
           PR_LOG(gSecureDocLog, PR_LOG_DEBUG, ("SecureUI:%p: Icon set to lock\n", this));
           
-          if (mSecurityButton)
-            res = mSecurityButton->SetAttribute(NS_LITERAL_STRING("level"),
-                                                NS_LITERAL_STRING("high"));
+          if (mSecurityButton) {
+            if (mSecurityState == (STATE_IS_SECURE|STATE_SECURE_HIGH)) {
+              res = mSecurityButton->SetAttribute(NS_LITERAL_STRING("level"),
+                                                  NS_LITERAL_STRING("high"));
+            } else {
+              res = mSecurityButton->SetAttribute(NS_LITERAL_STRING("level"),
+                                                  NS_LITERAL_STRING("low"));
+            }
+          }
           
           if (eventSink)
-            eventSink->OnSecurityChange(aRequest, (STATE_IS_SECURE));
+            eventSink->OnSecurityChange(aRequest, mSecurityState);
           
           if (!mSecurityButton)
             return res;
@@ -365,7 +373,7 @@ nsSecureBrowserUIImpl::OnStateChange(nsIWebProgress* aWebProgress,
   
   // don't need to do anything more if the page is broken or not secure...
   
-  if (mSecurityState != STATE_IS_SECURE)
+  if (!IS_SECURE(mSecurityState))
     return NS_OK;
   
   // A URL is starting to load...
@@ -472,7 +480,7 @@ nsSecureBrowserUIImpl::CheckProtocolContextSwitch(nsISecurityEventSink* eventSin
 
   // Check to see if we are going from a secure page to an insecure page
   if (newSecurityState == STATE_IS_INSECURE &&
-      (oldSecurityState == STATE_IS_SECURE ||
+      (IS_SECURE(oldSecurityState) ||
        oldSecurityState == STATE_IS_BROKEN)) {
 
     SetBrokenLockIcon(eventSink, aRequest, PR_TRUE);
@@ -481,12 +489,20 @@ nsSecureBrowserUIImpl::CheckProtocolContextSwitch(nsISecurityEventSink* eventSin
 
   }
   // check to see if we are going from an insecure page to a secure one.
-  else if ((newSecurityState == STATE_IS_SECURE ||
+  else if ((newSecurityState == (STATE_IS_SECURE|STATE_SECURE_HIGH) ||
             newSecurityState == STATE_IS_BROKEN) &&
            oldSecurityState == STATE_IS_INSECURE) {
-
     AlertEnteringSecure();
   }
+  // check to see if we are going from a strong or insecure page to a
+  // weak one.
+  else if ((IS_SECURE(newSecurityState) &&
+            newSecurityState != (STATE_IS_SECURE|STATE_SECURE_HIGH)) &&
+           (oldSecurityState == STATE_IS_INSECURE ||
+            oldSecurityState == (STATE_IS_SECURE|STATE_SECURE_HIGH))) {
+
+    AlertEnteringWeak();
+  }
   
   mSecurityState = newSecurityState;
   return NS_OK;
@@ -496,13 +512,13 @@ nsresult
 nsSecureBrowserUIImpl::CheckMixedContext(nsISecurityEventSink *eventSink,
                                          nsIRequest* aRequest, nsIChannel* aChannel)
 {
-  PRInt16 newSecurityState;
+  PRInt32 newSecurityState;
 
   newSecurityState = GetSecurityStateFromChannel(aChannel);
 
   if ((newSecurityState == STATE_IS_INSECURE ||
        newSecurityState == STATE_IS_BROKEN) &&
-      mSecurityState == STATE_IS_SECURE) {
+      IS_SECURE(mSecurityState)) {
     
     // work-around for bug 48515
     nsCOMPtr<nsIURI> aURI;
@@ -544,14 +560,14 @@ nsSecureBrowserUIImpl::CheckPost(nsIURI *actionURL, PRBool *okayToPost)
   
   // if we are posting to a secure link from a secure page, all is okay.
   if (secure &&
-      (mSecurityState == STATE_IS_SECURE ||
+      (IS_SECURE(mSecurityState) ||
        mSecurityState == STATE_IS_BROKEN)) {
     return NS_OK;
   }
     
   // posting to insecure webpage from a secure webpage.
   // NOTE: This test is inconsistant with the one above
-  if (!secure  && (mSecurityState == STATE_IS_SECURE)) {
+  if (!secure && IS_SECURE(mSecurityState)) {
     *okayToPost = ConfirmPostToInsecureFromSecure();
   } else {
     *okayToPost = ConfirmPostToInsecure();
@@ -671,6 +687,21 @@ AlertEnteringSecure()
   return;
 }
 
+void nsSecureBrowserUIImpl::
+AlertEnteringWeak()
+{
+  nsCOMPtr<nsISecurityWarningDialogs> dialogs;
+
+  GetNSSDialogs(NS_GET_IID(nsISecurityWarningDialogs), getter_AddRefs(dialogs));
+  if (!dialogs) return;
+
+  nsCOMPtr<nsIInterfaceRequestor> ctx = new nsUIContext(mWindow);
+
+  dialogs->AlertEnteringWeak(ctx);
+
+  return;
+}
+
 void nsSecureBrowserUIImpl::
 AlertLeavingSecure()
 {
diff --git a/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.h b/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.h
index 96cad8b4f68..2f67c2dcd73 100644
--- a/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.h
+++ b/mozilla/security/manager/ssl/src/nsSecureBrowserUIImpl.h
@@ -90,6 +90,7 @@ protected:
 
   // Alerts for security transitions
   void AlertEnteringSecure();
+  void AlertEnteringWeak();
   void AlertLeavingSecure();
   void AlertMixedMode();
   PRBool ConfirmPostToInsecure();