We are using iprint on SLES10 OES2 SP1 - when we try to print duplex on

a: OfficeJet L7780
b: Color Laser Jet CM3530 (PCL driver)

the duplex jobs were ignored.... well the frontside is printed.

If we print directly on the IP port - all printings are fine with
duplex. (IP_ouripadress raw 9100 smtp status enabled)

The command is: iprintgw PORT=RAW HOSTADDRESS=ouripaddress

Client is 5.12 - OS is WinXP SP3 fully patched.

Any clues?