Okay, I think I have figured this out.  I'm using the MATE desktop with no GNOME desktop installed on the system.  That invalidates a lot of fallback assumption that either GNOME or KDE is installed.  Further there is no /etc/sysconfig/desktop file to specify the preferred desktop.

The attempt to setup the session manager is as follows (on MY system):

1) xrdp-sesman invokes /etc/xrdp/startwm.sh
2) /etc/xrdp/startwm.sh: invokes /etc/X11/xinit/xinitrc because
   it exists, and ignores all of its other builtin session logic
3) /etc/X11/xinit/xinitrc: invokes /etc/X11/xinit/Xclients
4) /etc/X11/xinit/Xclients: can't find /etc/sysconfig/desktop, nor GNOME or
   KDE, nor /etc/X11/xinit/Xclients.d, nor twm, and so simply exits.

I chose to add /etc/sysconfig/desktop as the simplest solution regardless of
the user being logged in (vs user specific customization files - yikes!) and
added the following line:
   PREFERRED=mate-session

This startup logic is a big historical mess.  I got quite a chuckle out of
seeing twm listed.  I remember it was the hot new window manager 20+ years ago.

It's not clear who/how the default session should be selected, but the current
approach is obviously broken.  Some random notes:

1) xrdp/startwm.sh: on Fedora, this immediately delegates all work to xinitrc
2) xinitrc: grinds through all of the /etc/X11/xinit/xinitrc.d/* scripts,
   then on Fedora, assuming no $HOME/.Xclients, immediately delegates to
   Xclients.  I wonder why it is invoked a second time if the first one fails?
3) 

Issues
1) What is the best env symbol for a session manager?  DESKTOP, PREFERRED,
   DESKTOP-SESSION?  I see all three in different places. UGH.
2) These scripts are lousy with attempts to guess from hardcoded lists of
   known desktops, which seems like a really bad idea.  Reading a desktop
   neutral file (/etc/sysconfig/desktop) or scanning a desktop neutral list
   (e.g. /usr/share/xsessions) seems a much better idea.

Anyway, my immediate problem is solved.

Still a problem with Fedora-19.

# uname -a
Linux hpc16 3.10.9-200.fc19.x86_64 #1 SMP Wed Aug 21 19:27:58 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

# yum list xrdp
xrdp.x86_64    0.6.0-0.7.fc19

This message is a reminder that Fedora 18 is nearing its end of life.
Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 18. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
this bug will be closed as WONTFIX if it remains open with a Fedora 
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Fedora 18 changed to end-of-life (EOL) status on 2014-01-14. Fedora 18 is
no longer maintained, which means that it will not receive any further
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If you can reproduce this bug against a currently maintained version of
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I am having the same problem with Fedora-20.  Specifically with xrdp-0.6.0-0.8.fc20.x86_64

I also heve it on newle installe Fedora 20 mate spin.

Adding PREFERRED=mate-session into /etc/sysconfig/desktop as suggested in comment 1 solve problem.
So fix it should be not so hard.

This message is a reminder that Fedora 20 is nearing its end of life.
Approximately 4 (four) weeks from now Fedora will stop maintaining
and issuing updates for Fedora 20. It is Fedora's policy to close all
bug reports from releases that are no longer maintained. At that time
this bug will be closed as EOL if it remains open with a Fedora  'version'
of '20'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version.

Thank you for reporting this issue and we are sorry that we were not 
able to fix it before Fedora 20 is end of life. If you would still like 
to see this bug fixed and are able to reproduce it against a later version 
of Fedora, you are encouraged  change the 'version' to a later Fedora 
version prior this bug is closed as described in the policy above.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events. Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

Fedora 20 changed to end-of-life (EOL) status on 2015-06-23. Fedora 20 is
no longer maintained, which means that it will not receive any further
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of
Fedora please feel free to reopen this bug against that version. If you
are unable to reopen this bug, please file a new report against the
current release. If you experience problems, please add a comment to this
bug.

Thank you for reporting this bug and we are sorry it could not be fixed.

I am having the same problem with Fedora-21.  Specifically with  xrdp-0.6.1-10.fc21.x86_64

Reopening (after being closed due to F20 EOL), problem manifests in F21 as well.

hello, this bug will be fixed in newer version that will land fedora soon.

Two questions:
1) When will I be able to see the fix in a regular F22 yum update?
2) Can you point me at either the patchfile for the fix, or a high-level summary of what the corrective action was (so I can keep my older pre-F22 machines in line with the upcoming F22 fix)

Thanks
-- Charlie