Well, I could not figureout what that task does, but I removed it from my system.
In the task manager, in the Applications tab, you'll find "pup". Just right click on that and choose "Go To Process". It took me to one process named "9624880.exe". I searched my file system for this file and found it in C:\WINNT\system32\. It looked like a VB application. To my horror(I'm exagerrating) I found many such .exe files there such as 30295962.exe, 35219973.exe and 82117861.exe, all of which start an application called "pup" upon double click(execution). This program also creates a key in your registry "HKEY_LOCAL_MACHINE\SOFTWARE\pup"
There I found that it is related to a file called "winpup.exe" under "C:\Program Files\ddm". It looks like an unwanted and very stubborn application that is designed to open popup windows to some websites once in a while while you work. If it can do that, it can also send some of your secrets across the network to some mysterious site somewhere in the world.
I hope some computing gurus in this planet shed some loght on this issue.

-S

Moin,
this site will shed lots of light on your issue:
http://sarc.com/avcenter/venc/data/adware.winpup.html
MfG, Carl.