motorola c350 modem detection

i have PIV 1.8Ghz with 256mb ddr ram. i have windows xp & windows 98se installed on my pc. i want to use dial up connection using my mobile motorola c350. my problem is that i am unable to detect the motorola usb modem.on same pc on windows xp the modem is detected on com3 port. i tried to install it manually but it didn't work. what are com ports? how should i detect the com3 port in windows 98se? plz help me.

You need the right drivers for the cable. Windows98 doesnt have them so you need to run your installation cd on Windows 98

i have already installed usb drivers for the usb cable. still i am not able to detect the modem.

On the Windows 98 OS?

ya, i have already installed usb driver in windows 98 os. i hav also tried to install the modem manually.& in the device manager it shows question mark on c350 phone, what does it mean?