Tux Paint 0.9.6 was just released as source. Changes include:
Initial support for arbitrary window sizes.
(Add “#define SVGA” to src/tuxpaint.c and compile to test 800x600 mode)
New paintbrush colors added; some colors renamed
Fixed text tool bug when hitting [Enter] past the bottom of the screen
BeOS printing support code incorporated into main source tree
Saved-files directory can be specified at runtime with "–savedir"
command-line option, or “savedir=…” configuration file setting.
(Useful for Windows labs with homedirectory drives, e.g. “H:”)
More info on Tux Paint:
PS - In the next release, there’ll be a Japanese localization, and
hopefully, the 800x600 mode will be the default.