Windows Platform Wins CC EAL 4+ Certification
Infoworld reports "Both 32-bit and 64-bit versions of Windows Server 2003, Standard Edition with Service Pack 1; Windows Server 2003, Enterprise Edition with Service Pack 1; and Windows Datacenter Edition with Service Pack 1 have achieved Common Criteria (CC) Evaluation Assurance Level 4, Augmented with ALC_FLR.3 certification, said Mario Juarez, senior product manager in the Security Technology Unit at Microsoft. The certification is more commonly known as EAL 4+, with the "+" denoting the addition of the ALC_FLR.3 certification."
Read more here, and in the white paper.
Here is the press release, if you like that sort of thing.