Cannot get the RCX 1.0 to respond to IR remote control

Hi,

I have just got my son’s old RCX 1.0 out for my grandson and purchased a Lego (9738) IR remote control so he can control the RCX unit.

The RCX unit works OK and all the built in programs work OK but it does not respond to the remote control commands at all.

Firstly can somebody confirm wether the RCX 1.0 does work with the IR remote control and if so any idea how to get it working again?