ESET SS4 and Isass.exe

[northridge]

From what I understand from searching threads here, Isass.exe is a system file to do with logon and secirity issues.
It being shown up by ESET Smart Security 4 as containing Win32/Autoit/GPworm: so whats the deal: is it infected or not and what should I do about it?
Thanks

[stackz]

Windows\System32\Lsass.exe is a system file, Isass.exe is definitely not.