So does that mean that both the cross compiler and native compiling works
I compiled it natively so that the install is ok for on board development.
I really think that cross compiling will work without problems as Trolltech generally takes cross-compilation into account.
Note that you don't need a Zaurus to try cross-compilation.
I don't know exactly how long it took (something like 10 hours with distcc and a pentium 3 800Mhz). I also had to use a swap to link the debug libs. I have just done a ./configure; make install. (I think i don't have opengl built inside, because I didn't have the libs installed)