According to the iSync Device List, the Motorola C350 is supported by iSync. But my phone was not found.
There are small differences between the supported model and mine. Using USB Prober[1] my device announces itself as:
Device VendorID/ProductID: 0x22B8/0x5802 (Motorola PCS)
whereas iSync expects[2] a ProductID of 0x3802 for the C350.
Instead of editing the iSync plist file I created an iSync Plugin as Rui Carmo described in his detailed iSync Plugins Howto.
Copy the MotorolaC350a.phoneplugin folder into one of these folders:
Then plug the phone with the data cable, restart iSync and Add Device... and the phone should be found immediately.
Peter Steiner
unistein@gmx.ch
http://pesche.schlau.ch
[1] Installed as part of the Apple Developer Tools in /Developer/Applications/Utilities/USB Prober
[2] /Applications/iSync.app/Contents/PlugIns/ApplePhoneConduit.syncdevice/Contents/PlugIns/PhoneModelsSync.phoneplugin/Contents/Resources/MetaClasses.plist