Problem sharing a printer with Vista and XP computers

I have an HP LJ3030 all-in-one. For the past few years it has been
connected directly to WinXP Home computer #1, but connected indirectly
through a multi-port DSL modem connected to Computer #1 and also to my
second WinXP Home computer #2.

Worked fine on all three functions.

Now I've acquired a new Vista Ultimate 64 bit computer, and wish to connect
it as well.

Here's what HP tech support tells me. Yes, they have a Vista 64 bit driver.
But the printer is not networkable. Thus I can either connect it directly
to the Vista computer, and cut off the XP's, or vice versa.

Is there some other hardware or software solution, short of junking a
serviceable and expensive printer?

--

PT