mov, mp4 playback

[ferrous66]

to allow quicktime playback in my zoom player,
I have installed:

1- quicktime alternative (just quicktime codec, no MPC)
2- 3ivx delta4 which includes mov and mp4 splitter

I get:

1- .mov files playback perfectly
2- .mp4 give me an error

Why do mp4 files give me an error? I thought 3ivx includes an mp4 decoder...

So I installed envivio plugin and now it works...I still would prefer to keep it simple and have 3ivx work. Is it possible?

edit: 3ivx not necessary for .mov


Thanks