>I cannot get this to work, because any attempt at calling a function
>in mainprog results in an unresolved external.  I understand why I am
>getting this, but is there any way to get this to work?

Actually, as of MPEiX 5.5, you can use HPLOADPROC to bind backwards
through the program ... you'll need to do dynamic loading and calling
to make this work - it isn't automatic.

Take a look at http://docs.hp.com/mpeix/communicator/ix55/ct31900d.html