I'm newbe :-). I have problem with compiling qt on i386 to x86_64 architecture. My steps was:

1. configure:
./configure -embedded x86 -platform qws/linux-x86-g++ -xplatform qws/linux-x86_64-g++ -prefix /usr -sysconfdir /etc -shared -largefile -no-qt3support -no-phonon -no-webkit -no-script -no-scripttools -no-declarative -no-declarative-debug -opensource -big-endian -host-big-endian -no-javascript-jit

2. make
After make I've got error:

global/qt_pch.h:1: sorry, unimplemented: 64-bit mode not compiled in
make[1]: *** [.pch/release-shared-emb-x86/QtCore.gch/c++] Error 1
make[1]: Living directory `/root/openelec/SYSTEMS-DESIGN/build.SYSTEMS-DESIGN_EDEN-Intel_3D.x86_64-devel/qt-everywhere-opensource-src-4.7.4/src/corelib'
make: *** [sub-corelib-make_default-ordered] Error 2

I've tried to find something to solve my problem, but I've found only simple instruction which didn't help to me.
Could any of you help me?

Best regards