Well I'm running ubuntu on arm7 and had xrdp running nicely with tightvncserver, lxfe, then it stopped working, reporting a login error. Looking at the log for xrdp it seems to be fireing up Xvnc ok and logging in ok, then nothing.... the logs are exceptionally poor so I don't know exactly what it's doing at all.
Anyhow, if I run Xvnc in the terminal and edit /etc/rdp/rdp.ini to work on the correct port all is fine (except there's no windows manage or desktop environment variable setup, but that's more down to how Xvnc works more than anyting).. i still get a stock X desktop and can run xfe ok for some reason, it dosn't complan that it can't find the desktop like other X apps do. No password needed to do this.
I can also run vncserver, give it a password, edit /etc/rdp/rdp.ini and it works fine so long as I put the same password in when xrdp fires up.
both also run just fine with no parameters, so it seems the defaults are ok too.
So it seems like there's some problem with xrdp-sesman hooking up to Xvnc (tightvncserver), but I have no idea what that is...
any clues on how to diagnose this further or a possible solution to the problem?