I found I had to manually fixup my $PATH env var too like Qt/E page and unset $CC and $CXX when building qt 4.8 from source. Normally these are all set by our OE angstrom compiler when building SDK examples, but these had to be stripped when building full source tree.

One more item I ran into was with the 4.8.3 webkit option kept getting disabled by the configure script. I tracked this down to extra quotes in QMAKE_CXX setting which failed the gcc -dumpversion check. Don't know why the OE guys put their QMAKE_ vars all in quotes.