I see this is an old post but somebody might still need the info...
Ubuntu-2D is not available after ubuntu 12.10 so you cannot use it in conjunction with xrdp. if you are running ubuntu 12.10 or later, you have to modify the content of your .xsession file accordingly
to have xrdp working with ubuntu 12.10 and later, you will need to install a alternative desktop (xfce, lxde, mate-desktop,...)
You will then need to tell your system to use this new alternate desktop..To summarize the process,
- Step 1 : install xrdp (sudo apt-get install xrdp)
- Step 2 : install alternate desktop (let's say we want to use mate-desktop). Issue the following commands sudo apt-get update and then sudo apt-get install mate-core mate-desktop-environment mate-notification-daemon
- step 3 - tell your system to use the new desktop. Issue the following command echo mate-session >~/.xsession
you should be then good to go...
You can find detailed information about using xrdp and ubuntu 14.04 following this link (http://c-nergy.be/blog/?p=5382).
hope this help