You used symantecs online scanner i suppose ?

You can always send the file to Avast for examination. And they will update there database asap.

Or you can try to do a online scanner check with RAV :

http://www.ravantivirus.com/scan/indexie.php

But first try to kill the worm process in taskmanager : iexplorer.exe. pay attention not to kill iexplore.exe. (wich is your browser)

Symantec info about the virus :

http://securityresponse.symantec.com/avcenter/venc/data/w32.hllw.cult.c@mm.html

Waldo