diff --git a/mozilla/docshell/base/nsDocShell.cpp b/mozilla/docshell/base/nsDocShell.cpp
index 9862b80f9d6..c89855394d7 100644
--- a/mozilla/docshell/base/nsDocShell.cpp
+++ b/mozilla/docshell/base/nsDocShell.cpp
@@ -1108,10 +1108,15 @@ nsresult nsDocShell::FindTarget(const PRUnichar *aWindowTarget,
               target_muCV = do_QueryInterface(target_cv);            
               if (muCV && target_muCV) {
                 nsXPIDLString defaultCharset;
+                nsXPIDLString prevDocCharset;
                 rv = muCV->GetDefaultCharacterSet(getter_Copies(defaultCharset));
                 if(NS_SUCCEEDED(rv)) {
                   target_muCV->SetDefaultCharacterSet(defaultCharset);
                 }
+                rv = muCV->GetPrevDocCharacterSet(getter_Copies(prevDocCharset));
+                if(NS_SUCCEEDED(rv)) {
+                  target_muCV->SetPrevDocCharacterSet(prevDocCharset);
+                }
               }
             } 
         }