The last Maemo 4 trunk build I see is from September 16: http://ftp.mozilla.org/pub/mozilla.o...entral-maemo4/
It looks like mozilla-central nightly builds for Maemo 4 were turned off after that date.

That particular build is broken because of Mozilla bug 579186. You can launch it if you copy /usr/lib/libstdc++.so.6 from the Fremantle armel SDK to /opt/mozilla/fennec-2.0b1pre on your device, but the result (on my N800 running Diablo) is quite frankly something that's too slow to be usable.

EDIT: Looks like Maemo 4 support has been dropped: http://starkravingfinkle.org/blog/20...#comment-10489 . Supposedly they will take patches to fix things, though a cursory look at the bug suggests it could be a build environment issue, not a code issue.