See http://projects.blender.org/pipermail/bf-committers/2005-April/010506.html and projects.blender.org/pipermail/bf-committers/2006-December/017035.html A workaround was proposed by Kester Maddock http://projects.blender.org/pipermail/bf-committers/2005-April/010510.html and recently again, independently by Andreas Kasparz (no URL, private email) See also http://svn.python.org/projects/python/tags/r24c1/Include/pyport.h, starting line 430 : "On 4.4BSD-descendants, ctype functions serves the whole range of wchar_t character set rather than single byte code points only. This characteristic can break some operations of string object..."