GSM arduino connect to server failed (SOLVED)

I upload GSMwebClient example. GSM connect to the simcard then the status and net led turn off and GSM couldn't connect to server.

before it works well but now I can't figure out what happen.
I use arduino MEGA with GSM arduino.

First I used 12 volt power supply for my board, so the LEDs didn't turn off any more.

BUT I STILL HAVE ISSUE IN CONNECTION TO GSM BOARD.

I changed the "GSM3ShieldV1AccessProvider.cpp" :

		while(ready()==0)
		{			
			delay(500);
			ModemConfiguration(pin);
			delay(1000);		
		}

then it never stuck in this library .
I also try to figure out the same issue with "GSM3ShieldV1DataNetworkProvider.cpp"

I change the delay in "while(ready()==0)" to 1000 (instead of 100)
Also I add delay(15) below:

	else if(ct==10)
	{
		if(theGSM3ShieldV1ModemCore.genericParse_rsp(resp))
	    {   delay (15);
			if (resp) ....

then everything becomes fine..

I also changed the connection part in Arduino sketch :

 while (notConnected) {
      if (gsmAccess.begin(PINNUMBER) == GSM_READY)
      {     delay(500);
        if (gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY) {
              delay(500);
          notConnected = false;
        }
      }
    }

I am not professional in c++ and other programming languages..
So if anybody knows a better way please suggest it....

Thanks