Event ID 2004 using LPR

We rely heavily on LPR printing over a WAN to about 260 printers (Intel and Lantronics print servers). We recv a large # of 2004 errors on the NT print server (sp6a) and often a print queue will hang up with a stuck job. Usually, we have to reset the print server device, kill the stuck job and, on occasion, stop and restart the spooler.

I haven’t found anything relevant on MS’s KB and was hoping someone could give me some suggestions on how to correct this problem.
Thanks!