First , make shure your walls arent passable. After that , see if any other function might be making your player passable. And finaly , play with the my.fat / my.narrow flags. Also see if your player starts in the middle of that wall.

PS.:Your walls might be too thin , your model could have faces with wrong 'normals'. There could be another 20 reasons Try playing around with everything , because your script looks fine to me. And if you are using A6.4 or lower , try ent_move instead of c_move...