19) How does Motif work with X11R5?

Answer: Motif 1.1.X is only intended to be built with X11R4.  Motif 1.2.X is
for X11R5.  however, Motif 1.1.4 has been set to also work with X11R5.

For Motif 1.1.1, 1.1.2 and 1.1.3 you will need to compile Xlib and Xt with a
MOTIFBC flag set to YES (page 8, section 3.3 of the R5 release notes), or
you'll also have a link problem (LowerCase) and a fatal run time problem
(XContext manager).  If your applications come up with "Unknown keysym name:
osfActivate" errors, check the variable ProjectRoot. The name
/$PROJECTROOT/lib/XKeysymDB will have been wired into your Xlib.

In Motif 1.1.0, XtCallCallback uses NULL as the first argument instead of a
widget ID. This was ok under R4, but must be changed in the source for R5. It
was changed by OSF from Motif 1.1.1 onward.

Mrm won't work at all (can't link since it uses an X private variable that has
disappeared in R5).  Thre is an MIT patch that may fix this??  [I confess
ignorance of Mrm and UIL].