BSNL LG LSP 340E WLL phone (Serial Port )Not Connecting

Hi,
Frnds I'm using ubuntu 9.04 in my PC, My internet Connection is Bharat Sanchar Nigam Limited (BSNL) WLL Hi- Speed internet which uses LG LSP 340E Modem connecting through Serial port, which Works Well in Windows but it cant be accessed from Ubuntu, So Please Help me to Configure This Modem and connect to internet through Ubuntu, Please Note I'm a beginner in Linux..

:confused::confused::confused:
sory