If you are using XP only and Ubuntu the cups is already installed as well as everything you need to do IPP start
at >>Remote Printer Access in the first link, It will walk you the rest of the way through, no need use portage(and you can't anyway)
Hope that clarifies. The only thing you may need to do is enable CUPS webmin in Ubuntu as it is disabled by default.
A quick google search will tell you how to do that.
One good thing about this is then you can enter the IP address and port 631 from any pc in your network and manage your print server.
192.168.12.1:631 <-- for example
soule
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