diff --git a/mozilla/caps/include/nsCodebasePrincipal.h b/mozilla/caps/include/nsCodebasePrincipal.h
index 02795ccf9a5..710c54a6809 100644
--- a/mozilla/caps/include/nsCodebasePrincipal.h
+++ b/mozilla/caps/include/nsCodebasePrincipal.h
@@ -80,12 +80,14 @@ public:
 
     nsresult
     InitFromPersistent(const char* aPrefName, const char* aID, 
-                       const char* aGrantedList, const char* aDeniedList);
+                       const char* aGrantedList, const char* aDeniedList,
+                       PRBool aTrusted);
 
     virtual ~nsCodebasePrincipal(void);
     
 protected:
     nsCOMPtr<nsIURI> mURI;
+    PRBool mTrusted;
 };
 
 #endif // _NS_CODEBASE_PRINCIPAL_H_
diff --git a/mozilla/caps/src/nsCodebasePrincipal.cpp b/mozilla/caps/src/nsCodebasePrincipal.cpp
index 6610f6d5c03..a569fc43aac 100644
--- a/mozilla/caps/src/nsCodebasePrincipal.cpp
+++ b/mozilla/caps/src/nsCodebasePrincipal.cpp
@@ -106,24 +106,29 @@ NS_IMETHODIMP
 nsCodebasePrincipal::CanEnableCapability(const char *capability, 
                                          PRInt16 *result)
 {
-    static char pref[] = "signed.applets.codebase_principal_support";
-    nsresult rv;
-	nsCOMPtr<nsIPref> prefs(do_GetService("@mozilla.org/preferences;1", &rv));
-	if (NS_FAILED(rv))
-		return NS_ERROR_FAILURE;
-	PRBool enabled;
-    if (NS_FAILED(prefs->GetBoolPref(pref, &enabled)) || !enabled) 
-	{
-        // Deny unless subject is executing from file: or resource: 
-        PRBool isFile = PR_FALSE;
-        PRBool isRes = PR_FALSE;
+    // Either this principal must be preconfigured as a trusted source
+    // (mTrusted), or else the codebase principal pref must be enabled
+    if (!mTrusted)
+    {
+        static char pref[] = "signed.applets.codebase_principal_support";
+        nsresult rv;
+	    nsCOMPtr<nsIPref> prefs(do_GetService("@mozilla.org/preferences;1", &rv));
+	    if (NS_FAILED(rv))
+		    return NS_ERROR_FAILURE;
+	    PRBool enabled;
+        if (NS_FAILED(prefs->GetBoolPref(pref, &enabled)) || !enabled) 
+	    {
+            // Deny unless subject is executing from file: or resource: 
+            PRBool isFile = PR_FALSE;
+            PRBool isRes = PR_FALSE;
 
-        if (NS_FAILED(mURI->SchemeIs("file", &isFile)) || 
-            NS_FAILED(mURI->SchemeIs("resource", &isRes)) ||
-            (!isFile && !isRes))
-        {
-            *result = nsIPrincipal::ENABLE_DENIED;
-            return NS_OK;
+            if (NS_FAILED(mURI->SchemeIs("file", &isFile)) || 
+                NS_FAILED(mURI->SchemeIs("resource", &isRes)) ||
+                (!isFile && !isRes))
+            {
+                *result = nsIPrincipal::ENABLE_DENIED;
+                return NS_OK;
+            }
         }
     }
     nsBasePrincipal::CanEnableCapability(capability, result);
@@ -328,7 +333,7 @@ nsCodebasePrincipal::Write(nsIObjectOutputStream* aStream)
 // Constructor, Destructor, initialization //
 /////////////////////////////////////////////
 
-nsCodebasePrincipal::nsCodebasePrincipal()
+nsCodebasePrincipal::nsCodebasePrincipal() : mTrusted(PR_FALSE)
 {
     NS_INIT_ISUPPORTS();
 }
@@ -349,7 +354,8 @@ nsCodebasePrincipal::Init(nsIURI *uri)
 // This method overrides nsBasePrincipal::InitFromPersistent
 nsresult
 nsCodebasePrincipal::InitFromPersistent(const char* aPrefName, const char* aURLStr, 
-                                        const char* aGrantedList, const char* aDeniedList)
+                                        const char* aGrantedList, const char* aDeniedList,
+                                        PRBool aTrusted)
 {
     nsresult rv;
     nsCOMPtr<nsIURI> uri;
@@ -358,6 +364,8 @@ nsCodebasePrincipal::InitFromPersistent(const char* aPrefName, const char* aURLS
     if (NS_FAILED(rv)) return rv;
 
     if (NS_FAILED(Init(uri))) return NS_ERROR_FAILURE;
+    // XXX: Add check for trusted = SSL only here?
+    mTrusted = aTrusted;
 
     return nsBasePrincipal::InitFromPersistent(aPrefName, aURLStr, 
                                                aGrantedList, aDeniedList);
diff --git a/mozilla/caps/src/nsScriptSecurityManager.cpp b/mozilla/caps/src/nsScriptSecurityManager.cpp
index fd5aa9aa4e2..06ebae53cc1 100644
--- a/mozilla/caps/src/nsScriptSecurityManager.cpp
+++ b/mozilla/caps/src/nsScriptSecurityManager.cpp
@@ -2527,13 +2527,18 @@ nsScriptSecurityManager::InitPrincipals(PRUint32 aPrefCount, const char** aPrefN
                                         nsISecurityPref* aSecurityPref)
 {
     /* This is the principal preference syntax:
-     * capability.principal.[codebase|certificate].<name>.[id|granted|denied]
+     * capability.principal.[codebase|codebaseTrusted|certificate].<name>.[id|granted|denied]
      * For example:
      * user_pref("capability.principal.certificate.p1.id","12:34:AB:CD");
      * user_pref("capability.principal.certificate.p1.granted","Capability1 Capability2");
      * user_pref("capability.principal.certificate.p1.denied","Capability3");
      */
 
+    /* codebaseTrusted means a codebase principal that can enable capabilities even if
+     * codebase principals are disabled. Don't use trustedCodebase except with unspoofable
+     * URLs such as HTTPS URLs.
+     */
+
     static const char idSuffix[] = ".id";
     for (PRUint32 c = 0; c < aPrefCount; c++)
     {
@@ -2573,8 +2578,9 @@ nsScriptSecurityManager::InitPrincipals(PRUint32 aPrefCount, const char** aPrefN
         }
 
         //-- Create a principal based on the prefs
-        static const char certificateName[] = "capability.principal.certificate.";
-        static const char codebaseName[] = "capability.principal.codebase.";
+        static const char certificateName[] = "capability.principal.certificate";
+        static const char codebaseName[] = "capability.principal.codebase";
+        static const char codebaseTrustedName[] = "capability.principal.codebaseTrusted";
         nsCOMPtr<nsIPrincipal> principal;
         if (PL_strncmp(aPrefNames[c], certificateName,
                        sizeof(certificateName)-1) == 0)
@@ -2593,8 +2599,11 @@ nsScriptSecurityManager::InitPrincipals(PRUint32 aPrefCount, const char** aPrefN
             nsCodebasePrincipal *codebase = new nsCodebasePrincipal();
             if (codebase) {
                 NS_ADDREF(codebase);
+                PRBool trusted = (PL_strncmp(aPrefNames[c], codebaseTrustedName,
+                                             sizeof(codebaseTrustedName)-1) == 0);
                 if (NS_SUCCEEDED(codebase->InitFromPersistent(aPrefNames[c], id,
-                                                              grantedList, deniedList)))
+                                                              grantedList, deniedList,
+                                                              trusted)))
                     principal = do_QueryInterface((nsBasePrincipal*)codebase);
                 NS_RELEASE(codebase);
             }