In no particular order:
* John Pedersen, from John Wiley & Sons, Inc.
for his detailed and constant feedback about high-quality rendering,
combining characters and usage of TeX fonts. He's also been the first
one compiling the tool under Solaris.
* Claudio Sacerdoti Coen,
for his bug-reports and useful feedback for the GTK+ interface and
the implementation of the <maction> element (toggle mode). He's also
contributed into the development of various bindings for the OCaml
language.
* Pouria Masoudi
porting to GTK2 and Bonobo Control for GtkMathView
* Nathan Hurst
feedback for cursor API
* Shuying Wang
read-from-buffer methods in widget and gmetadom frontend
* Jean Brefort
patches for configure.ac and auto/Makefile.am
* Hubert Figuere (hub), Francis James Franklin (fjf)
MacOSX/fink port
* Robert Staudinger
autopackage support
* Marc Maurer (uwog)
Win32/mingw port
* Alessandro Appeddu
MathML to SVG converter
* Nicola Rossi
PostScript backend and accents