I tried something funny.. I took the definition of the orthographic projection(from the red book) and loaded up a calculated matrix as the projection matrix.

Though it didn't give the same result as using built in methods.. i had to multiply a translation to the calculated orthographic projection matrix because the coords 0,0 was lower right coordinates... yepp RIGHT =D

Now i wonder if someone tried this out, is there some matematical stuff going on that isn't specified in the docs. Seems a bit odd that i had multiply by a translation matrix to get the same results as the built in glOrtho.