Rainer Wichmann <rwichmann@hs.uni-hamburg.de>

  * most of everything

Markus Kuster <kuster@astro.uni-tuebingen.de>

  * OpenGL stuff

Patrick Risse <risse@astro.uni-tuebingen.de>

  * Accretion disk

Hans Schwengeler <schweng@astro.unibas.ch>
 
  * tested compilation on DEC/OSF1, helped with compile flags for PGPLOT

Roger Dingledine <arma@mit.edu>

  * pointed out a segfault in the 'info' routine

Andrew <santini@globalnet.co.uk>

  * pointed out the existence of faulty GNUPLOT versions

tenthumbs <10@dhyp6-131.cybernex.net>

  * found a 'Broken pipe' error with GNUPLOT

Ceoldo Costantino < inverness1 [at] virgilio dot it >

  * contributed the italian translation