Hello Sam,
As promised in the loki newsgroup, you'll find two sample case of
blitting failing with two offscreen surfaces.
testGL load an image on a surface A, blit it on another surface B, and
then use B to construct an OpenGL texture. Only Red channel is OK.
showimage loads an image in a surface A, blit it on another B, and
blit B, then A, on the screen. A is correct, not B.
Be aware that I’m having some hardware related problems on my PC
actually (caugh sig 11 when compiling). Maybe the cause of the bug. Tell
me if all is OK for you, even if it would be bad news for my hardware 
Franck.
PS : files in tar archive
Makefile
testgl.c
showimage.c
toto.bmp --> the test image, done with gimp, correctly displayed with
xv.
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