This is from the Microsoft Office website:

Will Microsoft Office SharePoint Server 2007 run on a 64-bit version of
Microsoft Windows?

Windows SharePoint Services 3.0, Office SharePoint Server 2007, Office Forms
Server 2007, and Office SharePoint Server 2007 for Search will support 64-bit
versions of Windows Server 2003.

So the answer is: Yes.
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S.Y.M. Wong-A-Ton