It does make sense when you say it; I have had a couple of other addons give me trouble lately aswell, so it may very well be a problem bigger than just Prat.
Have anyone checked out the new version 3.6.23 that came out a couple of hours ago?
EDIT: Prat-3.0-3.6.23 seem to work fine here, no errors after login atleast =)
Same here, 10 errors in anything 3.6.20 or higher. 3.6.19 works fine for me aswell =)