[Zope] Upgrading 2.5.0 -> 2.5.1 with source upgrader

Hi, I downloaded and unarchived the 2.5.0 -> 2.5.1 source patch at the proper location. This patch contains C source files, and I did'nt see any indication to compile those files. Running "python wo_pcgi.py" raises errors and does not the job because of ".py" files from CMF skins cannot be compiled to .pyc or .pyo ("return" outside of a function/method) How can I complete the installation ? Did I miss something ? Thanks in advance. My config : FreeBSD 4.5 and Python 2.1.3 --Gilles