Adapter Pda Cable

If i get USB 2.0 TO RS232 SERIAL will this connect to my modem?? or will i require and extension too?

http://cgi.ebay.ie/USB-2-0-TO-RS232-SERIAL-DB9-9-PIN-ADAPTER-CABLE-PDA-GPS_W0QQitemZ120441993005QQcmdZViewItemQQptZUK_Computing_CablesConnectors_RL?hash=item1c0ae6f72d&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1301%7C240%3A1308%7C301%3A1%7C293%3A1%7C294%3A50
yes it has a serial port

Hi - USBNow sell USB to RS232 (serial cables) - see the link below

This one is a 9 and 25 Pin male option (it has pins so will fit if your modem is female)

Bluetooth RS232 adapter setup and configuration