For what it's worth, I had a similar problem with my Epson 3800 - it would print about 14 inches into a print, and then the print job would die.
I did some network diagnostics, and discovered that one of my network switches would only pass about every third packet through. Replacing that switch solved the problem (and gave me a nice network performance boost as a bonus).
The reason it took a while for me to figure out the problem, is that TCP will retry packets quite a few times before it gives up and closes the socket - so until I actually traced some packets, the inherent reliability of TCP made it seem like the network was fine.