Disk Partitioning for Win 2003 Server

I’m looking for a disk partitioning tool/utility for Windows 2003 server. I bought an IBM basic server and it partitioned my server with a 4G C Drive and now I’m running out of space. Its an EIDE HD so its very basic. Symantec has a product called Volume Manager but it only supports Win 2000 and they have no plans on Win 2003. What can I do to increase my 4G Partition without taking down my server thats in production at a small site? Thanks for the help.