Not sure if you ever got this resolved, but I just had a user with the same type of problem and was able to fix it. Since yours is a jailbroken phone I'm not sure if that is causing your problem since the one I was able to fix is a legit AT&T phone, but it might be worth a try since it's not listed here. I just posted a blog entry for this too in case anyone is interested, you can find it here:
http://techierambles.blogspot.com/20...n-windows.html.
Connect the phone to the computer, then go into Device Manager. Go down and expand USB Controllers, then right-click on Apple Mobile Device USB Driver and choose Update Driver. Select to install automatically, then let it do its thing.
The setup this worked for was an iPhone 3G (AT&T), iTunes 8.2, and XP Pro SP3. Until I did this, the iPhone kept showing up as just a digital camera, and iTunes would give an error saying it found an iPhone but wasn't able to recognize it correctly. That went away as soon as the driver was updated. Good luck!