you can use REAL motif (there are a few), rather than lesstif
(you can find motif-3.2.4 and cde - though 3.2.4 is not compat with motif 2.n apps and has no fvwm style desktop panner)
lesstiff has more bugs than motif , also it uses name libXm.so but is incompatible with the REAL libXm.so lesstiff causes problems with some expensive well know shelf products that need "motif". all (debian/ubantu/other) linux used lesstif, and those apps must be recompiled to use motif (or use LD_LIBRARY_PATH to avoid the libXm.so naming conflict)
i would not suggest lesstif now that "the real thing" is released publicly unless re-releasing something to work within those distros, licensing aside.