I had a similar problem with a Galaxy S runnint CM7. The problem was caused by partition /datadata being full.
You can check this by running this command as root:
If you see % used = 100 then this is you problem.
Just move ...
OK so since the KC1 modems are hard to find for Cyanogen I will upload one that I created. Basically if you want to create your own, you have to get one of the radio packages (doesn't matter which, I grabbed anyone) then grab a legit copy of KC1 ...