LPD PROBLEM - strange artifact

Hi, I have SuSE Linux on PC with lprold running as spooler for two networked TCP/IP laser printers. Everything lpd does is just routing files to the printers from Samba clients. Time to time all Windows workstations tell in spool window that printing is paused. Resume or restart of spooled documents (in Windows) does not work. Status file in lpd spool folder informs that lpd is sending data, however, printer does not receiving anything. TCP/IP is OK for sure. What could be the problem? Thanks in advance. Andrei