Use Plone's safe_encode method instead of encode() to make sure unicode encoded strings can be indexed too.

svn path=/plone.app.discussion/trunk/; revision=51432

CHANGES.txt

@@ -8,6 +8,10 @@ Changelog
   fixes http://dev.plone.org/plone/ticket/11298.
   [timo]
 
+- Use Plone's safe_encode method instead of encode() to make sure unicode 
+  encoded strings can be indexed too.
+  [timo]
+
 
 2.0.7 (2011-07-15)
 ------------------

plone/app/discussion/catalog.py

@@ -10,6 +10,8 @@ from DateTime import DateTime
 
 from Products.CMFCore.interfaces import IContentish
 
+from Products.CMFPlone.utils import safe_unicode
+
 from Products.ZCatalog.interfaces import IZCatalog
 
 from plone.app.discussion.interfaces import IConversation, IComment
@@ -70,7 +72,7 @@ def title(object):
 
 @indexer(IComment)
 def creator(object):
-    return object.creator and object.creator.encode('utf-8')
+    return object.creator and safe_unicode(object.creator)
 
 @indexer(IComment)
 def description(object):