user-agent pollution .NET CLR 3.5.30729

Don't know when this started but currently the Firefox user-agent string is polluted by new a new addition "(.NET CLR 3.5.30729)".

Mozilla/5.0 (Windows; U; Windows NT 5.1; de; rv:1.9.0.9) Gecko/2009040821 Firefox/3.0.9 (.NET CLR 3.5.30729)

Maybe the new add-on "Microsoft .NET Framework Assistant" is to blame.

But although I disabled it the user-agent string was not reverted to normal.

Who gave Microsoft the right to blurt about the fact that .NET3.5 is installed on my computer?! Well, others are not better: If the Azigo Selector is installed then it adds itself to the user-agent string too.

Maybe SUN should add the installed Java version and whether OpenOffice is installed, and Adobe the installed Acrobat Reader version and the Flash version, and Apple the Quicktime and iTunes version and ...