flock of animals

i have an animal that i want to duplicate like a flock. then the flock starts moving on a plane and stops in front of a door. the door opens and they (about 30) goes through the door-opening. thats it…
i have looked at particle emitters such as boids and newtonians but it seems to go nuts. i cant control the movement of the flock. i have also heard about blender people, but it wont work on 2.49b.

does anyone have any good recipies or ideas?

help would very much be appreciated.