Wonderfull behavior of 6600 in outgoing call listener

Hi,
I just want to detect an outgoing call disconnect it then make a new call,
but when the run reaches to Dial method the iStatus of my RunL encounter with an error, -9 (KErrOverFlow),

what does it mean,
I am running the code on Nokia 6600,

The RunL code:

+++++++++++++++++

       if (iStatus == KErrNone)
        {
           if (iCallStatus == RCall::EStatusHangingUp  || iCallStatus == RCall::EStatusIdle || iCallStatus == RCall::EStatusUnknown)
           {
             iCall.Close();
             if(iFlag )
             {
               TBuf <100> newCallName;
               iCall.OpenNewCall(iLine, newCallName);
               iCall.Dial(_L("03656655"));
            }
           }
           else if(iCallStatus == RCall::EStatusDialling)
           {
             if(iFlag )
             {
               iFlag = false;
             }
             else
             {
               iFlag = true;
               RLine::TLineInfo lineInfo;
               iLine.GetInfo(lineInfo);
               iCall.OpenExistingCall(iLine, lineInfo.iNameOfLastCallAdded);
               iCall.HangUp();
             }
           }          
       
           iLine.NotifyStatusChange(iStatus, iCallStatus);
           SetActive();
        }
        else
        {
           WriteToFile(iStatus.Int());
        }


+++++++++++++

Is there any Idea?  this code works correctly on nokia3650 and SEP900,...
If the red line be in comment, the code works correctly, but when it calls here the -9 occured in iStatus,,,
and also the Dial method itself returns 0 which means KErrNone... !!!

Thanks