I didn't clearly delineate my prose from the excerpts in the previous message.  The following paragraphs were just me:
I mined the following stuff from New Project Registration pages:
From the Terms of Service (http://sourceforge.net/register/tos.php)
Though the terms of service would appear to allow code in the CVS of a
project having different OSI approved licenses, there is a concept of a
project having one declared license.

It would probably be best to provide a moderately detailed proposal of what
the task would do and what other software and licenses would be involved to
execute the task and post it here and on the SourceForge Licensing Forum
https://sourceforge.net/forum/forum.php?forum_id=25232 for discussion.
So if the task is

a) essentially running the GNU program (invoking methods on a class would
seem to be equivalent)

b) can reasonably considered independent.  So no GPL'd code intertwined or
embedded in the source for the task, obviously.  Not requiring access to the
GPL code (ie using reflection) to build would also help in preserving the
"independence" of the task.

If this task is essentially "running" the gnu regular expression library,
then it seems analogous to a cpp task running gcc.  Though obviously
knowledge of the command line args of gcc is required to build a gcc task,
that doesn't make the gcc task a derived work from the gcc source code.