bitpim won't detect my VX6100

Bitpim can't detect my phone. I have an LG VX6100, a usb cable I bought from www.cellphoneshop.net, and bitpim 7.34. I've installed the usb cable's driver which shows up as "Prolific usb-to-serial comm port(COM6)" in device manager and bitpim's "SETTINGS > BROWSE > CHOOSE A COMM PORT" window. On my phone, I've tried going to "MENU > SETTINGS > DATA SETTINGS > PC CONNECTION" and switching the setting between USB and RS-232C(Com port) and neither setting seems to help bitpim in detecting my phone.(By the way, should the setting be on USB or RS-232C com port?) Do I need to change any other setting on my phone? Please help.