If you are a Microsoft Certified Systems Administrator (MCSA) or a Microsoft Certified Systems Engineer (MCSE) on Windows Server 2003, you can now transfer your skills to achieve multiple Microsoft Certified Technology Specialist (MCTS) certifications or Microsoft Certified IT Professional (MCITP) credentials on Windows Server 2008.

For the first time, the transition path is available before the product release. If you have a Windows Server 2008 certification on your resumé, you have an excellent opportunity to catch the eye of early adopter organizations. Microsoft Learning developed this transition path to recognize the investment and expertise you have demonstrated throughout your certification history—don’t miss your chance to take advantage of these new certifications.

Your path consists of one exam, which allows you to earn multiple Microsoft Certified Technology Specialist (MCTS) certifications on Windows Server 2008.
-First step: Take one exam to earn MCTS certification on Windows Server 2008

From there, you can complete the remaining requirements for one or both of the Microsoft Certified IT Professional (MCITP) certifications for Windows Server 2008.
-Your transition path from MCSA on Windows Server 2003 to MCITP 
-Your transition path from MCSE on Windows Server 2003 to MCITP

Because there is a significant technology gap between Windows 2000 Server and Windows Server 2008, only IT professionals with specific Microsoft Certifications on Windows Server 2003 can utilize these transition or upgrade paths. In addition, there is no upgrade path from messaging or security specializations to Windows Server 2008 certifications.

 Check out all the details here:
Thanks Microsoft