OpenOffice on Amiga is impossible, just like Mozilla. Why? It uses too much of linux, to put it simply. You'd have to port maybe dozens of external parts OpenOffice uses. Replacing them is pointless: it would be almost as much work as coding a fully featured office from scratch.
Anyone wanting to port it will at very least have to port the GUI kits or wrap them to native GUIs (which don't have all the features you need, so you'd have to implement them manually). Then they'd have to implement APIs and features that AmigaOS doesn't have, the infamous Fork() being the simplest.
It's not a big task - it's an enormous task. There is no-one left who has the time and the skill, and there is too little code infrastructure to help them.
