Index: nsXPITriggerInfo.cpp
===================================================================
RCS file: /cvsroot/mozilla/xpinstall/src/nsXPITriggerInfo.cpp,v
retrieving revision 1.39
diff -up -r1.39 nsXPITriggerInfo.cpp
--- nsXPITriggerInfo.cpp
+++ nsXPITriggerInfo.cpp
@@ -92,23 +92,10 @@ nsXPITriggerItem::nsXPITriggerItem( cons
     }
 
     // parse optional hash into its parts
-    if (aHash)
+    if (aHash && PL_strchr(aHash, ':'))
     {
         mHashFound = PR_TRUE;
-
-        char * colon = PL_strchr(aHash, ':');
-        if (colon)
-        {
-            mHasher = do_CreateInstance("@mozilla.org/security/hash;1");
-            if (!mHasher) return;
-            
-            *colon = '\0'; // null the colon so that aHash is just the type.
-            nsresult rv = mHasher->InitWithString(nsDependentCString(aHash));
-            *colon = ':';  // restore the colon
-
-            if (NS_SUCCEEDED(rv))
-                mHash = colon+1;
-        }
+        mHash = nsDependentCString(aHash);
     }
 }
 
Index: nsXPInstallManager.cpp
===================================================================
RCS file: /cvsroot/mozilla/xpinstall/src/nsXPInstallManager.cpp,v
retrieving revision 1.156
diff -up -r1.156 nsXPInstallManager.cpp
--- nsXPInstallManager.cpp
+++ nsXPInstallManager.cpp
@@ -761,17 +761,46 @@ NS_IMETHODIMP nsXPInstallManager::Downlo
             }
 
             // If there was hash info in the trigger, but
-            // there wasn't a hash object created, then the
-            // algorithm used isn't known.
+            // there wasn't a hash object created, then
+            // mHash is the value to use to initialize the
+            // mHasher.
 
             if (mItem->mHashFound && !mItem->mHasher)
             {
-                // report failure
-                mTriggers->SendStatus( mItem->mURL.get(), nsInstall::INVALID_HASH_TYPE );
-                if (mDlg)
-                    mDlg->OnStateChange( i, nsIXPIProgressDialog::INSTALL_DONE,
-                                         nsInstall::INVALID_HASH_TYPE );
-                continue;
+                PRBool ok = mItem->mHash.IsEmpty();
+                PRInt32 colon = mItem->mHash.FindChar(':');
+                if (!ok && colon > 0) {
+                    nsCOMPtr<nsICryptoItem> hasher(do_CreateInstance("@mozilla.org/security/hash;1"));
+
+                    if (hasher) {
+                        rv = hasher->InitWithString(Substring(mItem->mHash,
+                                                              0, colon - 1));
+                        if (NS_SUCCEEDED(rv)) {
+                            mItem->mHash = Substring(mItem->mHash,
+                                                     colon + 1,
+                                                     mItem->mHash.Length());
+                        } else {
+                            hasher = nsnull;
+                        }
+                    }
+                    if (hasher) {
+                        mItem->mHasher = hasher;
+                    } else {
+                        mItem->mHash.Truncate();
+                        ok = PR_FALSE;
+                    }
+                }
+                if (!ok) {
+                    // report failure
+                    mTriggers->SendStatus( mItem->mURL.get(),
+                                           nsInstall::INVALID_HASH_TYPE );
+                    if (mDlg)
+                        mDlg->OnStateChange( i,
+                                             nsIXPIProgressDialog::INSTALL_DONE,
+                                             nsInstall::INVALID_HASH_TYPE );
+                    continue;
+                }
+              
             }
 
             // Don't install if we can't verify the hash (if specified)