temporary fix:

# emerge --sync
# emerge -C qt
# emerge =x11-libs/qt-3*
# vi /usr/portage/profiles/package.mask

insert :

=x11-libs/qt-4*

remember – everytime you "emerge --sync", package.mask gets overwritten with a new copy.

again, this is just a temporary fix

edit : tested not working fully , i will provide an update