Is it (Apart from being spoofed) ?:
Mozilla/4.0 (compatible; MSIE 7.0b; Windows NT 5.1; .NET CLR 1.0.3705; .NET CLR 1.1.4322)
Except for the .NET stuff… IS IE7 dependant on the .NET Framework?
Just some thoughts… Anyhow, anyone building around a useragent-string isn’t doing the right thing. 🙂