RANTS: Connecting to a Windows 7 machine from RDP on OS X

The basics:
- OS X.4.11
- PowerPC G5 machine
- Remote Desktop Connection Client for Mac v2.0.1
- Connecting to a Windows 7 64-bit machine with latest RDP client

The symptoms:
- Connection can be made to Windows 7 machine
- Mouse functions work normally
- As soon as a key is pressed on the keyboard of the G5, the RDP client on the G5 quits.
- Problem does not seem to be the Windows 7 machine, as I can connect to it from an Intel-based Mac.

Guess:
- Problem likely has to do with that the G5 is a PowerPC processor. Any guesses?