diff -r 27f946cfe350 -r 59e89db3a67d web/views/schema.py
--- a/web/views/schema.py	Wed Sep 30 18:03:53 2015 +0200
+++ b/web/views/schema.py	Wed Sep 30 18:04:27 2015 +0200
@@ -26,6 +26,8 @@
 import os, os.path as osp
 import codecs
 
+from six import text_type
+
 from logilab.common.graph import GraphGenerator, DotBackend
 from logilab.common.ureports import Section, Table
 from logilab.common.registry import yes
@@ -279,7 +281,7 @@
     def cell_call(self, row, col):
         defaultval = self.cw_rset.rows[row][col]
         if defaultval is not None:
-            self.w(unicode(self.cw_rset.rows[row][col].unzpickle()))
+            self.w(text_type(self.cw_rset.rows[row][col].unzpickle()))
 
 class CWETypeRelationCardinalityCell(baseviews.FinalView):
     __regid__ = 'etype-rel-cardinality-cell'
@@ -487,7 +489,7 @@
         entity = self.cw_rset.get_entity(row, col)
         rschema = self._cw.vreg.schema.rschema(entity.rtype.name)
         rdef = rschema.rdefs[(entity.stype.name, entity.otype.name)]
-        constraints = [xml_escape(unicode(c)) for c in getattr(rdef, 'constraints')]
+        constraints = [xml_escape(text_type(c)) for c in getattr(rdef, 'constraints')]
         self.w(u'<br/>'.join(constraints))
 
 class CWAttributeOptionsCell(EntityView):