Microsoft EULA stokes crusade

Microsoft's new crusade against licenses that enforce source-code sharing has reached the EULA of their Mobile Internet Toolkit. It even disallows the use of any "Publicly Available Software" tool in the production of software using this SDK. This seems to be a very wide ranging restriction applying to compilers (gcc), editors (vim, staroffice), filesystems (backup on linux server), web-browsers (mozilla logging into some online tool provider), Java (sun's virtual machine). The licenses covered include: the GPL and LGPL, the Artistic License (e.g., PERL), the Mozilla Public License, the Netscape Public License, the Sun Community Source License (SCSL), and the Sun Industry Standards License (SISL). Is this legal? Thanks to Jonathan for the link. Update: 06/26 05:42 PM by S : Here's a legal opinion on the matter.