[Nov 2009]:

Comodo Internet Security may claim that pstill.exe and gpstill.exe are infected 
by Heur.molebx. This is a false alarm. 

PStill uses anti-tempering mechanisms that cause the heuristic warning to flag 
it wrongly. In this case just tell Comodo Antivir to add pstill.exe and gpstill.exe to the list of 'safe files'.

[June 2002]:

Certain antivirus software claims that the PStill distribution is infected,
please read this text to find out what is going on here and how to resolve 
the issue:

Cited from http://www2.arnes.si/~sopjsimo/gimp/: [external link]

(~Certain versions of Sophos antivirus claim that the files are infected
with with the Momma-B trojan (when they are not), response by Sophos:)

"This is almost certainly a case where the user has downloaded the
standard version of Sophos without the IDE files.

There is an issue with detection of Troj/Momma-B on the standard version
of 3.58 which is resolved with the IDE file which was published on our
website at: http://www.sophos.com/virusinfo/analyses/trojmommab.html on
the 21st of May.

Regards,

Michael Lynch
Sophos Support"