1.Connect with bsnlnet. Disconnect and immediately connect back with blackberry apn.
2.Use older version of mobile partner as it allows quicker shift from one apn to other. The shift should be quick.
3.Once it connects to blackberry apn, open whatever VPN you are using. It may connect.
4.If it does not connect , disconnect and again try that 'bsnlnet to blackberry' method.
After 4 or 5 times vpn will discover an open port ( either 52 or 53) and connect.
