I am using the French Canadian keyboard layout on Ubuntu Lucid and was having a hard time typing "\". Solution:
- With "Terminal Server Client" GUI and on the "Local Resources" tab, set the keyboard to "ca-fr".
- Note it's "ca-fr" and not "fr-ca" or "fr_CA" or whatever wrong values I could come up with..!
- With rdesktop, it's "rdesktop -k fr-ca <hostip>".
- Note it's "fr-ca" there and not "ca-fr" or "fr_CA". +1 for consistency. Oh well...
Update
Forget about tsclient and rdesktop, I never fully got them to work correctly. Remmina works much better for me. It is based on FreeRDP that uses sane keyboard input. Simply install its ppa since Ubuntu Lucid's version is too old.