Some days ago I've updated to Ubuntu Lucid and I had this bug and unfortunately I don't know how to resolve it!

I have this service POLKITD started with the system. It's consuming a lot of memory as long it is running (less after 30 minutes, >400MB after 1 hour) also the CPU is staying at 50% all the time, and even more.
I don't know what this service do (although here it's saying what polkitd is).

I've tried
start-stop-daemon -K -n polkit
update-rc.d -f polkitd remove
but after boot is still appearing!

Now, as I write this my system is running for 1h 30 min and polkit is 500MB of RAM.

My question is: HOW to stop/kill/murder this service???!

Thank you!