Issues with Tata Photon [3G USB Dongle]

Guys,

I configured dialer settings via Wvdialconfig & wvdial but still not able to browse using Ice weasel & Chrome.

. I am able to get IP address & primary/secondary DNS server via ISP. This means dialer is set-up correct over USB2 ttyl.
. I am able to ping google.com via IP as well as hostname.
. Dig & NSlookup returns good results.
. Everything works over wi-fi connection but not over dongle.
. wget shows machine sending http request but I never get a response.
. iptable or no other firewall. proxy set to none.
. Wireshark shows browser sending a get request but no response from server. At max, i see a '"previous TCP segment was lost" message.

so my routes, dns and dialer config looks all fine but somehow browsing still doesn't work with default settings. I tried with Open DNS servers as well but no avail as its not a dNS issue.
What else could be? I searched entire forum but couldn't find anything.
Apologies for not pasting evidenence for above points as I am posting from other machine in office right now.