I have a similar question.

I got an answer from another forum entirely, but haven't
had time to try it yet. Here it is, since neither of us
has gotten an answer here:

"you may want to not capture the port until AFTER you log
onto term serve... you can actually utilize a network
printer or any other port type with terminal services by
adding this key to your registry (on the client machine)
under
LOCAL_MACHINE/SOFTWARE/MICROSOFT/TERMINAL_SERVICES_CLIENT
add a key called FilterQueueType .. then right click that
new key and go to New dword value... give it a value of
ffffffff and then close out of the registry... you may
have to reboot but it might work right out of the box...
you will then have access to any printer regardless of
port type... then term serve over and find the printer
and THEN capture the port... printing from dos should
then work... can you tell ive been thru this before? heh"

It doesn't sound quite right to me, because the capture
is still going to be of TSXXX something, which seems to
be the confusing part for both you and I. I'm also
considering trying \\machinename\TSXXX, and then I'm
going to try actually sharing the printer on the server.
I dunno whether that will work with the way things get
disconnected when one logs off ...