diff --git a/weboob/tools/value.py b/weboob/tools/value.py
index 001709b6..6e8bb3ee 100644
--- a/weboob/tools/value.py
+++ b/weboob/tools/value.py
@@ -89,7 +89,7 @@ class Value(object):
             raise ValueError('Value can\'t be empty')
         if self.regexp is not None and not re.match(self.regexp, unicode(v)):
             raise ValueError('Value "%s" does not match regexp "%s"' % (v, self.regexp))
-        if self.choices is not None and not v in self.choices.iterkeys():
+        if self.choices is not None and not v.lower() in map(str.lower, self.choices.iterkeys()):
             raise ValueError('Value "%s" is not in list: %s' % (
                 v, ', '.join(unicode(s) for s in self.choices.iterkeys())))