building 32-bit PyQT4 and matplotlib on X86_64

[enricong at gmail.com]

I'm having some issues attempting to build PyQT4 and matplotlib.  I'm
on a 64-bit machine and am trying to build a 32-bit version.  I have
already installed seperate 32-bit libs and a 32-bit version of python
however I continue to run into two basic problems

With PyQT4, I dont know how to tell it that I want to compile 32bit.
I run into a problem at the very beginning when it runts qtdirs.mk and
there -m32 isnt there.  I tried adding it in and manually running
make, but then I have the second problem

with matplotlib and PyQT4, eventhough the "-m32" flag is being used
with g++ and /usr/lib is included in the library search path, I run
into problems where I get a message saying something like:

/usr/bin/ld: skipping incompatible /usr/lib64/libz.so when searching
for -lz
then
/usr/bin/ld: cannot find -lz

I had this exact problem with a few modules while trying to build
Python 32 bit, however I was able to substitude -lz with the full path
to the library /usr/lib/libz.so.1

This would be impractical to do with matplotlib.
This is also just one example, I have problems with other libraries
too.