What cabling is required to connect serial modem to PortServerTS1

have purchased and installed with drivers a PortServerTS1 the COM port is showing in device manager however cant communicate with modem attached to PortServer.
US Robotics V.92 56K modem 25 pin at modem end converted to 9 pin this cable worked fine when connecting directly to a test machine however now plugged in via RJ45 to port server and RJ45-9 pin serial adaptor communication has stopped.
using a straight RJ45 patch cable at present, is a cross over of special cabling required?

A straight through cable would be used. If using an 8 pin cable, the altpin setting would need to be applied under the Serial Port > Advanced Serial Settings > Enable DCD on 8-pin RJ45 connectors (Altpin).

The pin-outs can be found here:

http://ftp1.digi.com/support/cabling/modem_rj45_8pin_altpin_db25m.pdf