Description:
I got the package on http://archlinux.c3sl.ufpr.br/testing/os/x86_64/python-numpy-1.5.0-1-x86_64.pkg.tar.xz and extract. When I did a ''grep -rin 'usr/bin/env python' .'' I found it:

./lib/python2.7/site-packages/numpy/tools/py3tool.py:1:#!/usr/bin/env python23

This ER solve the problem.

find $pkgdir -name '*.py' -exec sed -i -e "s|#![ ]*/usr/bin/python$|#!/usr/bin/python2|" \
-e "s|#![ ]*/usr/bin/env python$|#!/usr/bin/env python2|"\
{} \;

And with the ER used actually on PKGBUILD is impossible be used on python-2.6.5, as you can see:

sed: can't read /home/robinho/tmp/arch/pkg/usr/lib/python2.7/site-packages/numpy/*.py: No such file or directory
sed: can't read /home/robinho/tmp/arch/pkg/usr/lib/python2.7/site-packages/numpy/*/*.py: No such file or directory
sed: can't read /home/robinho/tmp/arch/pkg/usr/lib/python2.7/site-packages/numpy/*/*/*.py: No such file or directory
sed: can't read /home/robinho/tmp/arch/pkg/usr/lib/python2.7/site-packages/numpy/*/*/*/*.py: No such file or directory

I don't know why, but using this PKGBUILD http://pastie.org/private/fgdzkqkdn0tvragmq4zjg, on usr/bin there are 2 scripts: f2py2 and f2py. Because it, a did this ER:

find $pkgdir/usr/bin -exec sed -i -e "s|#![ ]*/usr/bin/python$|#!/usr/bin/python2|" \
-e "s|#![ ]*/usr/bin/env python$|#!/usr/bin/env python2|"\
{} \;


Maybe putting the '[ ]*' to grantee the ER will check the spaces after the python and python2 is good!
But, is need be careful when are using 's@env python@env python2@', because it can change "env python3" to "env python23"

Thanks