No pull-up or WPU... the i/o is set as an output and set to low and AN INT happen???? huh???? I must miss something here!

Maybe i'm blind... but i don't see any cod in here... so i would assume the TRIS register haven't been changed. Try LOW PORTA.5 instead.. if this work.. it just mean you didn't at least changed TRISA setting....or the INT don't care about the TRIS... i'll check the datasheet...