Check the location of the system shared libraries.
The shared libraries libXt.a and libX11.a are normally stored in /usr/lpp/X11/lib/R5. The libXm.a library is normally located in either /usr/lpp/X11/Motif1.2/lib or /usr/lpp/X11/R5/Motif1.2.
If these shared libraries are located in directories different from the above, set the LIBPATH environment variable to indicate these other directories.
See “Environment variables” for instructions on how to set LIBPATH.