BB Curve :: Cannot Connect Over Wifi On Digisol Router

I have Blackberry curve 9380. Recently I purchased Digisol Broadband router model DG-BG4011N which I am using with BSNL Broadband connection. The trouble is I cant use this wifi connection on my Blackberry. My blackberry discovers this connection, asks for a passpharase and connects to wifi. It even displays on homesvreen as connected but stil I cannot use internet over wifi. Everytime when I access browser, App world etc, the connection being used is my mobile EDGE connection. When I try to use only wifi by disconnecting from Bsnl network, it will give me error. I contacted Digisol helpline, but they also could not help. I have tried changing security on my digisol interface from WPA only to WPA2 and to auto mode, but still cannot use internet over wifi on my Blackberry. Wifi works fine on my laptop. Also my blacberry works fine over wifi at a friends place.