Hi,

> gcc -o xopps -O2 -fpic activity.o beware.o bitmaps.o chart.o chdate.o color.o dialog.o drawing.o dynarray.o event.o export.o fileio.o filemenu.o gr_plot.o help.o hline.o image.o internals.o level.o line.o main.o marker.o menu_calls.o message.o mover.o mxutil.o object.o page.o pline.o plot.o print.o rectlist.o sactivity.o selectfile.o sequence.o shellmgmt.o slip.o status.o symbol.o text.o utc.o util.o        -L/usr/local/lib -lXm -L/usr/X11R6/lib -lXt -lX11 
> ld: -lXm: no match
> make: *** [xopps] Error 1

What version of lesstif are you using? If it's the lesstif-0.75a version,
then remove the character 'a' from the end of the library. 

Just a thought,

> Other things compile happily.

Using the Xm library? If so, then I don't have a clue. But you
could use ktrace/kdump to find out what ld is trying to do and
why it doesn't find the library.

  Guenther