The gsl-library is since version 1.0 stable and for general use.
More information about it at http://sources.redhat.com/gsl/.
Nearly all modules are wrapped. The sum and hankel modules have been
wrapped. But noone responded to the request of support (providing an example,
test the code for proper functioning)
The code is quite stable now XXX
You can download it here: http://sourceforge.net/projects/pygsl
Release 0.2, documentation updated on January, 2005.