We're having an issue with iPrint on nw6.0 sp4. every so often if a
printer jams or is out of paper or goes offline for whatever reason the
NDPS printer agent will show that status even if after the printer
returns to a ready state (even hours later). The only thing that I can
do to fix the problem is to shutdown & restart the Printer Agent. Then
the printer will start printing.

I've seen this happen with multiple HP printers, this morning it
happened to a 4050, which has the most recent JetDirect firmware.

Any ideas? It so frustrating.