Please remember to CC: the maintainer next time. You can find that info in the Portfile or via the 'port' command.
Can you do:
sudo port clean qt4-mac
sudo port build qt4-mac [+variants as you see fit] [+other options]
and then attach the logfile as stated (assuming it errors out again) as well as the command line you used for the "build". I really don't have enough to go off of from what you've posted. The target "first" is always available in Qt's top-level Makefile, so possibly the Makefile wasn't generated correctly by qmake.
Also please include: What is your Mac's OS & make? Are you installing qt4-mac from scratch, or upgrading?