It's tricky but can be done as I do it at work. You need to setup the USB printer for sharing - don't forget to turn on file and printer sharing. Once it is setup for sharing, open a command prompt as administartor. Now type this:
net use lpt1: \\<your computer name>\<printer share name> /PERSISTENT:YES
If the command is done properly, you should now be able to print. This just redirects the lpt1 port to the printer.
NOTE: I edited this to bold the command line since this should all be one line, but the forum is wrapping it.