I upgraded to 2.06 a little bit ago on a server and it's crashing under two situations...
1) If a user uploads a .message file (this seems like an easy to do mistake) further uploads into the directory result in a crash.
2) A power failure resulted in .ioftpd.zs being filed with zeros. This caused further uploads into this directory to result in a crash.
Clearly the 2nd case isn't common, but it shouldn't crash. It should just trigger a rescan, and the continue on from there. The race may be incorrect, but the directory will be OK.
The .message issue is bad.
I'd prefer a .ini settings file as well.
BigBoxer:
http://www.syberhosting.com/iozs/ is where I got my copy.