Well, since StarOffice and Mozilla can both be compiled with gcc, and AmigaDE uses gcc as its compiler, there won't be any compiler issues (except possibly gcc 3.x issues with the newest versions of StarOffice and Mozilla) but there are plenty of other issues, mostly having to do with completely different API's between the two systems. StarOffice and Mozilla have both been ported already to a wide range of systems which means that certain issues have already been worked out.
I think the chances of seeing it on OS4 are very, very slim however. OS5/AmigaDE is a different beast entirely.
I think it's inevitable that both will be ported to that system, especially Mozilla. The best approach with Mozilla is to write a browser "shell" from scratch (any takers?) and then port gecko, the rendering engine to it, like Galeon. There is a lot of good reasons to do so, not least of which is that it would be good to bring Mozilla to PDA's as well. Star Office is a much "harder sell" so to speak, much, much harder to port (especially with a native look-and-feel) and fewer potential users. I think it's a safe bet that Sun isn't going to do it, no matter how useful it might be to the Amiga to have it.
But I think we can be sure of an "AmiMoz" eventually being ported, especially with a "Galeon" type approach, there might already be work in this direction.
As for StarOffice, best idea would be just to run X-Windows on the AmigaDE environment and then compile StarOffice onto that. That's how it works at the moment for Mac OS X, though eventually Mac OS X will have a native port.
