Remote Desktop problem?

I have been having a problem with one of my computers in my house, where... It can see out but cannot be seen, on RDC.

I can access my main comp- XP pro 64bit, via the said comp, but cannot access the computer from my xp-pro comp.

The said computer is running XP home 32bit and when I check to try and allow incoming requests, I dont have that option, only the option to allow requests to be sent out. Any help is appreciated.