buildout explodes when distribute is installed

I needed to generate some python 2.5 eggs, so installed distribute from pypi.

Now, buildout explodes:

Traceback (most recent call last):
  File "/home/stub/lp/lp-sourcedeps/eggs/zc.buildout-1.5.0dev_gary_r110073-py2.5.egg/zc/buildout/buildout.py", line 1734, in main
    getattr(buildout, command)(args)
  File "/home/stub/lp/lp-sourcedeps/eggs/zc.buildout-1.5.0dev_gary_r110073-py2.5.egg/zc/buildout/buildout.py", line 416, in bootstrap
    reqs=['zc.buildout'])
  File "/home/stub/lp/lp-sourcedeps/eggs/zc.buildout-1.5.0dev_gary_r110073-py2.5.egg/zc/buildout/easy_install.py", line 1187, in sitepackage_safe_scripts
    include_site_packages, relative_paths))
  File "/home/stub/lp/lp-sourcedeps/eggs/zc.buildout-1.5.0dev_gary_r110073-py2.5.egg/zc/buildout/easy_install.py", line 1597, in _generate_site
    (real_site_path, site_path))
RuntimeError: Buildout did not successfully rewrite /usr/lib/python2.5/site-packages/distribute-0.6.10-py2.5.egg/site.py to /home/stub/lp/trivial/parts/buildout/site.py