I have printing delay in the network. It takes many time ( Between 10 Min to one hour ) for simple file for printing it. If file has picture it takes more.
We use Linux Mandriva 2005, 2006, 2007 and some Windows XP. But it happens for all of them. This issue happened some days not every day.
All Printers have 84 MB Memory print Server and static IP and Print Server model are “HP Jetdirect 620n” .

Printer Models are:
HP Laser Jet 4250
HP Laser Jet 1500
HP Color Laser Jet 4650

We changed printer, Print Servers as well but it didn't solved.

I found one solution but i cant do it every they. Those printers have 2 slot for installing “HP Jetdirect 620n Print Server” , Just i changed printserver slot. After this change, they work properly.

Is there any body to help me? ASAP

Have you tried tracking communication between the printers and your client machine? It should show if the work was accepted or not (and when).

How Can I track communication?

Is there any Built In command in Linux for this issue?

Well...kind of. They communicate via network, so network monitoring tool will do. You can try with ethereal/wireshark. If you haven't used any such tool, you may just see who sends and when. That should help locating the problem.