I got a new phone (yay!) and since I can't afford a smart phone data plan, it's not an android (not so yay). It's a samsung Gravity Touch (SGH-T669).

I've been trying to find some sort of software that supports even basic connectivity with the phone. If I can get even a simple command line tool, I can write the other software layers to do what I actually want (tie it in to KDE4's Akonadi so I can sync it seamlessly with my online contacts and calendar from Google).

The only program I can find for phone sync that still seems to be worked on regularly is BitPim, which is CDMA only. I've pinged their list, and they either have no interest in supporting GSM phones, or the hardware is different enough between the two that they can't. The response was very curt.

Any advice for where to look for syncing capability for that phone? Or anyone familiar with USB protocol sniffing/hacking that wants to teach me what I need to know to sort it out for myself?

(To mods: I have no idea if this is in the right place. I was torn between hardware and software. Please move it if I got it wrong)

As you guessed, BitPIM is only for CDMA phones, a completely different technology than GSM. Asking the BitPim developers why they don't support GSM hardware is a bit like asking the Gentoo maintainers why they don't add support for using Debian packages. The concept between the two is the same, but the execution is completely different.

With GSM phones, there are a few different protocols in use for things like syncing, so there is a lot of fragmentation in terms of the software used. If there is no software yet confirmed to work with your phone, you are going to be in uncharted territory. You might want to start with Gammu, your phone isn't listed as supported yet, but Gammu is compatible with many phones and is a good a place to start as any.