finding packages installed from a 3rd party repository

[Karl Goetz]

hi all
I'm trying to find all packages i installed from a certain 3rd party 
repository, as i think they are causing some instability.
i suspect there is something in the apt toolkit, but I'm not sure what 
it is. any pointers? :)
kk

-- 
Karl Goetz
The buck stops there -> $
Australian Ubuntu users team - http://wiki.ubuntu.com/AustralianTeam