How can I indirectly access a server that only allows connections from certain IP addresses?

Question

I need to connect to a Windows Server 2003 machine at work from a Windows 7 machine at home via remote deskop. The problem is, the server is set up so that only a very restricted range of IP addresses is allowed to connect to the server. For a few weeks I will be unable to physically access the machine to change these settings, so I'm screwed unless I can somehow spoof my own IP address into one that the server allows.

I know this sounds shady and variations on this question have probably been asked a million times, but it's not like I need to break into this server. I have full administrator rights to the machine, I just can't connect to the machine from outside the work network.

Is there any way to do this? Thanks for any help.