diff --git a/openerp/osv/expression.py b/openerp/osv/expression.py
index d471f7efb4f..23c22f10b8b 100644
--- a/openerp/osv/expression.py
+++ b/openerp/osv/expression.py
@@ -1012,7 +1012,7 @@ class expression(object):
 
             else:
                 if field._type == 'datetime' and right and len(right) == 10:
-                    if operator in ('>', '>='):
+                    if operator in ('>', '>=', '='):
                         right += ' 00:00:00'
                     elif operator in ('<', '<='):
                         right += ' 23:59:59'