If the user says it's ok to use their locale, use it so we get a correct value for preferred encoding. Printing localized dates is not possible without this.

mdboom · mdboom · commit c7c275d756b8 · 2011-08-01T10:54:20.000-04:00
diff --git a/lib/matplotlib/cbook.py b/lib/matplotlib/cbook.py
@@ -29,13 +29,15 @@
 # side effects.  Passing False eliminates those side effects.
 
 try:
-    preferredencoding = locale.getpreferredencoding(False).strip()
+    preferredencoding = locale.getpreferredencoding(
+        matplotlib.rcParams['axes.formatter.use_locale']).strip()
     if not preferredencoding:
         preferredencoding = None
 except (ValueError, ImportError, AttributeError):
     preferredencoding = None
 
 def unicode_safe(s):
+    print preferredencoding, type(s)
     if preferredencoding is None: return unicode(s)
     else: return unicode(s, preferredencoding)
 
