qt4-x11 and x11prefix

[Jeremy Huddleston]

qt4-x11's qmake is causing built applications to use /usr/X11 instead  
of /opt/local for X11... This has caused some problems here, and I'm  
sure others might see it too:

./src/lib/animations/triangletriad_0001/Makefile:DEFINES       = - 
D__USE_WS_X11__ -DUSE_DLOPEN
./src/lib/animations/triangletriad_0001/Makefile:INCPATH       = -I/ 
opt/local/libexec/qt4-x11/mkspecs/darwin-g++ -I. -I../.. -I.. -I/usr/ 
X11/include
./src/lib/animations/triangletriad_0001/Makefile:LIBS          = $ 
(SUBLIBS)  -L/usr/X11/lib -L../../../../lib -lpgl -lGLU -lGL

So to summarize, the qt libs themselves are linked against /opt/local/ 
lib/..., but applications that are built with the qmake build system  
are not.

--Jeremy