Hello,
as Microsoft provides also help and fixes for Office 2003/2007 on Windows server 20008 R2 i would say yes, it is supported. Here is an example about
http://support.microsoft.com/kb/2498855 and keep in mind that you may have multiple problems/errors that may occur in that combination from Office 2003 on Windows server 2008 R2.
Best regards
Meinolf Weber
MVP, MCP, MCTS
Microsoft MVP - Directory Services
My Blog: http://msmvps.com/blogs/mweber/
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