diff --git a/mozilla/caps/src/nsScriptSecurityManager.cpp b/mozilla/caps/src/nsScriptSecurityManager.cpp
index 9d37c056fb7..491dd7c2034 100644
--- a/mozilla/caps/src/nsScriptSecurityManager.cpp
+++ b/mozilla/caps/src/nsScriptSecurityManager.cpp
@@ -2141,6 +2141,7 @@ nsScriptSecurityManager::CheckConfirmDialog(JSContext* cx, nsIPrincipal* aPrinci
 
     PRInt32 buttonPressed = 1; // If the user exits by clicking the close box, assume No (button 1)
     rv = prompter->ConfirmEx(title.get(), message.get(),
+                             (nsIPrompt::BUTTON_POS_1_DEFAULT) +
                              (nsIPrompt::BUTTON_TITLE_YES * nsIPrompt::BUTTON_POS_0) +
                              (nsIPrompt::BUTTON_TITLE_NO * nsIPrompt::BUTTON_POS_1),
                              nsnull, nsnull, nsnull, check.get(), checkValue, &buttonPressed);
diff --git a/mozilla/embedding/components/windowwatcher/public/nsIPromptService.idl b/mozilla/embedding/components/windowwatcher/public/nsIPromptService.idl
index 5daeeaef625..bf85da3bb4e 100644
--- a/mozilla/embedding/components/windowwatcher/public/nsIPromptService.idl
+++ b/mozilla/embedding/components/windowwatcher/public/nsIPromptService.idl
@@ -130,7 +130,11 @@ interface nsIPromptService : nsISupports
   const unsigned long BUTTON_TITLE_REVERT        = 7;
 
   const unsigned long BUTTON_TITLE_IS_STRING     = 127;
-   
+  
+  const unsigned long BUTTON_POS_0_DEFAULT       = 0 << 24;
+  const unsigned long BUTTON_POS_1_DEFAULT       = 1 << 24;
+  const unsigned long BUTTON_POS_2_DEFAULT       = 2 << 24;    
+  
   const unsigned long STD_OK_CANCEL_BUTTONS      = (BUTTON_TITLE_OK * BUTTON_POS_0) +
                                                     (BUTTON_TITLE_CANCEL * BUTTON_POS_1);
 
diff --git a/mozilla/embedding/components/windowwatcher/public/nsPIPromptService.idl b/mozilla/embedding/components/windowwatcher/public/nsPIPromptService.idl
index 6c687142b7d..28ecc6560b9 100644
--- a/mozilla/embedding/components/windowwatcher/public/nsPIPromptService.idl
+++ b/mozilla/embedding/components/windowwatcher/public/nsPIPromptService.idl
@@ -52,7 +52,7 @@ interface nsPIPromptService : nsISupports
         eButton0Text=8, eButton1Text=9, eButton2Text=10, eButton3Text=11,
         eDialogTitle=12};
   enum {eButtonPressed=0, eCheckboxState=1, eNumberButtons=2,
-        eNumberEditfields=3, eEditField1Password=4};
+        eNumberEditfields=3, eEditField1Password=4, eDefaultButton=5};
 %}
 
    void doDialog(in nsIDOMWindow aParent, in nsIDialogParamBlock aParamBlock, in string aChromeURL);
diff --git a/mozilla/embedding/components/windowwatcher/src/nsPromptService.cpp b/mozilla/embedding/components/windowwatcher/src/nsPromptService.cpp
index 243b0f94015..22042f95a9d 100644
--- a/mozilla/embedding/components/windowwatcher/src/nsPromptService.cpp
+++ b/mozilla/embedding/components/windowwatcher/src/nsPromptService.cpp
@@ -287,7 +287,10 @@ nsPromptService::ConfirmEx(nsIDOMWindow *parent,
   
   int buttonIDs[] = { eButton0Text, eButton1Text, eButton2Text };
   const PRUnichar* buttonStrings[] = { button0Title, button1Title, button2Title };
-  
+
+#define BUTTON_DEFAULT_MASK 0x03000000
+
+  block->SetInt(eDefaultButton, (buttonFlags & BUTTON_DEFAULT_MASK) >> 24);
   PRInt32 numberButtons = 0;
   for (int i = 0; i < 3; i++) { 
     
diff --git a/mozilla/netwerk/base/public/nsIPrompt.idl b/mozilla/netwerk/base/public/nsIPrompt.idl
index 116f2c5f9e7..d5087c7b2d2 100644
--- a/mozilla/netwerk/base/public/nsIPrompt.idl
+++ b/mozilla/netwerk/base/public/nsIPrompt.idl
@@ -84,6 +84,10 @@ interface nsIPrompt : nsISupports
     const unsigned long BUTTON_TITLE_REVERT        = 7;
 
     const unsigned long BUTTON_TITLE_IS_STRING     = 127;
+    
+    const unsigned long BUTTON_POS_0_DEFAULT       = 0 << 24;
+    const unsigned long BUTTON_POS_1_DEFAULT       = 1 << 24;
+    const unsigned long BUTTON_POS_2_DEFAULT       = 2 << 24;    
    
     const unsigned long STD_OK_CANCEL_BUTTONS      = (BUTTON_TITLE_OK * BUTTON_POS_0) +
                                                     (BUTTON_TITLE_CANCEL * BUTTON_POS_1);
diff --git a/mozilla/xpfe/global/resources/content/commonDialog.js b/mozilla/xpfe/global/resources/content/commonDialog.js
index 6e738cee1cb..eae83751020 100644
--- a/mozilla/xpfe/global/resources/content/commonDialog.js
+++ b/mozilla/xpfe/global/resources/content/commonDialog.js
@@ -135,7 +135,6 @@ function commonDialogOnLoad()
     iconClass = "message-icon";
   iconElement.setAttribute("class", iconElement.getAttribute("class") + " " + iconClass);
 
-  var firstButton = document.documentElement.getButton("accept");
   switch (nButtons) {
     case 4:
       setLabelForNode(document.documentElement.getButton("extra2"), gCommonDialogParam.GetString(11));
@@ -152,7 +151,7 @@ function commonDialogOnLoad()
     case 1:
       string = gCommonDialogParam.GetString(8);
       if (string)
-        setLabelForNode(firstButton, string);
+        setLabelForNode(document.documentElement.getButton("accept"), string);
       break;
   }
 
@@ -163,7 +162,24 @@ function commonDialogOnLoad()
   setCheckbox(gCommonDialogParam.GetString(1), gCommonDialogParam.GetInt(1));
 
   if (gCommonDialogParam.GetInt(3) == 0) // If no text fields
-    firstButton.focus(); // Don't focus checkbox, focus first button instead
+  {
+    var defaultButton = gCommonDialogParam.GetInt(5);
+    switch (defaultButton) {
+      case 3:
+        document.documentElement.getButton("extra2").focus();
+        break;
+      case 2:
+        document.documentElement.getButton("extra1").focus();
+        break;
+      case 1:
+        document.documentElement.getButton("cancel").focus();
+        break;
+      default:
+      case 0:
+        document.documentElement.getButton("accept").focus();
+        break;
+    }
+  }
 
   getAttention();
 }