Hm. If you are using Virtual Server you have quite a few options available to redirect serial output.
Named pipes are commonly used for debugging.. set the named pipe up with syntax like:
\\.\pipe\<name>
Then fire up your debugger on the host machine with:
windbg [-y SymbolPath] -k com

ipe,port=\\.\pipe\PipeName[,resets=0][,reconnect]
Virtual Server also lets you redirect com ports to a text file which might be more useful.
If you are trying to somehow make something output to a serial port, the "mode" command in Windows might do what you are after. check it out.
Honestly I don't really think I'm following you at all though

sorry!