Problem with updatePortf

Friends

I am running into trouble with updatePortf.

Stepping through it the problem is with the call to .updatePosPL, but I
cannot debug that function.

I am working on a small example that exhibits the problem but in the
mean time is there a way I can debug .updatePosPL?

cheers
Worik

it does not matter                      I think that I shall never see
how much I dig and dig                    A billboard lovely as a tree
this hole just                      Indeed, unless the billboards fall
keeps getting deeper                      I'll never see a tree at all