diff --git a/VERSION b/VERSION
index 6674efce..71226a50 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-Version 2.5.1-stable+timestamp.2013.06.25.15.39.19
+Version 2.5.1-stable+timestamp.2013.06.25.16.55.36
diff --git a/gluon/dal.py b/gluon/dal.py
index cb9f7e97..8862167f 100644
--- a/gluon/dal.py
+++ b/gluon/dal.py
@@ -1069,12 +1069,13 @@ class BaseAdapter(ConnectionPool):
                     drop_expr = 'ALTER TABLE %s DROP %s;'
                 else:
                     drop_expr = 'ALTER TABLE %s DROP COLUMN %s;'
-                query = ['ALTER TABLE %s ADD %s__tmp %s;' % (t, key, tt),
-                         'UPDATE %s SET %s__tmp=%s;' % (t, key, key),
+                key_tmp = key + '__tmp'
+                query = ['ALTER TABLE %s ADD %s %s;' % (t, key_tmp, tt),
+                         'UPDATE %s SET %s=%s;' % (t, key_tmp, key),
                          drop_expr % (t, key),
                          'ALTER TABLE %s ADD %s %s;' % (t, key, tt),
-                         'UPDATE %s SET %s=%s__tmp;' % (t, key, key),
-                         drop_expr % (t, key)]
+                         'UPDATE %s SET %s=%s;' % (t, key, key_tmp),
+                         drop_expr % (t, key_tmp)]
                 metadata_change = True
             elif sql_fields[key]['type'] != sql_fields_old[key]['type']:
                 sql_fields_current[key] = sql_fields[key]