Just to feed your paranoia, I routinely scan and cabs or installers I get here with:
http://www.virustotal.com/
This does 42 different scans on your files and has come up with positives from this site. I did not install those cabs. Some of the positives may refer to the packing programs, I am not sure, but it is bothersome and as far as I could tell some were real viruses. I think you are at much more risk running an exe installer on your PC that alleges it installs a cab.
The best way to feed paranoia is to listen to the Security Now podcast on the TWIT network:
http://twit.tv/sn243
Listen to this and you will turn off Java scripting on your PC....
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Sprint: G1000, HTC-6600, 6800, TP2 now Optimus S with Stock Android 2.2.2.