Jørgen Berntsen writes:
 > > I need to evaluate several bessels functions with complex arguments, but
 > > can only find bessel functions with real arguments. Have I missed
 > > something or is there a way around this problem?

We're looking for a volunteer to implement them, I think, only the
real case is available in GSL 1.0.  The standard reference for the
complex versions is the D.Amos paper in ACM TOMS v12, although there
might be better algorithms available now since that was published in
1986.

regards
Brian Gough