Update Snom screen for roaming users?

Just hoping that someone might be able to set me off down the right path for this one.

I would like to be able to add something in the FreePBX code or make a custom app that runs when users log in or out, and updates Snom 360/370 idle screen to reflect the appropriate state the phone is in.

I was thinking of using Snom’s new XML minibrowser and AGI script, but am not entirely sure of how I can implement something like that above. Or even if that idea is correct or not.

If anyone has any pointers, I would really appreciate it.