I made some progress with the port to OpenBSD. It seems it is pricky about includes and so I made several includes using CFLAGS etc.
the last "attempt" had the computer munching for half the afternoon just to get the following:
gcc -I/usr/X11R6/include -I/usr/local/include -I/usr/local/include/libpng -funsigned-char -o blender -Wl,--export-dynamic -L/usr/X11R6/lib -L/usr/local/lib -L/usr/local/include/libpng -L/usr/local/lib/python2.2/config source/.libs/libblender_source.al intern/bsp/.libs/libblender_BSP.al intern/decimation/.libs/libblender_LOD.al intern/ghost/.libs/libblender_GHOST.al intern/string/.libs/libblender_STR.al intern/guardedalloc/.libs/libblender_guardedalloc.al intern/bmfont/.libs/libblender_BMF.al intern/container/.libs/libblender_CTR.al intern/memutil/.libs/libblender_MEM.al intern/keymaker/.libs/libblender_belgium.al intern/iksolver/.libs/libblender_IK.al intern/moto/.libs/libblender_MT.al intern/python/frozen/libfrozen.a -lpython2.2 -lGLU -lGL -lX11 -lXext -lutil -ljpeg -lpng -lcrypto -lpthread -lstdc++ -lz -Wl,-rpath,/usr/local/lib -Wl,-rpath,/usr/local/lib
/usr/local/lib/libpython2.2.so.0.0: warning: tempnam() possibly used unsafely; consider using mkstemp()
/usr/local/lib/libpython2.2.so.0.0: warning: tmpnam() possibly used unsafely; consider using mkstemp()
intern/ghost/.libs/libblender_GHOST.al(GHOST_ISystem.lo): In function `GHOST_ISystem::createSystem(void)':
GHOST_ISystem.lo(.text+0x58): undefined reference to `GHOST_SystemX11::GHOST_SystemX11(void)'
collect2: ld returned 1 exit status
here my wisdom ends, since the unresolved symbol is from blender itself.
OpenBSD 3.3 is using gcc 2.95.3 and I installed gnu make
Check your config.log for the results of 'checking for X'
(ie is X11 autodetected?)