Hi Rob G,
The new SH devices include a port interrupt circuitry which is very similar to the keyboard interrupt module. One of the differences between these two modules is the hability to control the pulling devices independently (no matter they are enabled as port interrupt sources or not).
All you have to do is to enable the respective PTxPE bit and select the desired pulling device through PTxES (1 = pull-up, 0 = pull-down).
Best regards,