Christian should really release that code then.
A bit off topic but... - That was a "port" of gtksourceview to get it compiling on windows by xxOes - and it is available on his site (gnope should probably provide a link somewhere - had to troll the php-gtk-dev list for a link). Basically it involved writing in all the dllexport declarations by hand and creating a msvc project for it - this shouldn't be needed anymore though because tml (Tor Lillqvist) did some heavy lifting to get gtksourceview ported to windows properly as of version 1.5.5 - mingw/msys will compile it fine, just turn off the libgnomeprint stuff in configure (since it will be moving to 2.10's gtk print system anyway) - you can even get precompiled windows binaries for it on ftp.gnome.org (along with the rest of gnome if you're so inclined)