diff --git a/gluon/dal.py b/gluon/dal.py
index c794f612..2506e1c5 100644
--- a/gluon/dal.py
+++ b/gluon/dal.py
@@ -32,7 +32,7 @@ def _default_validators(db, field):
     field_type, field_length = field.type, field.length
     requires = []
 
-    if field.options is not None and field.requires:
+    if isinstance(field.options, list) and field.requires:
         requires = validators.IS_IN_SET(field.options, multiple=field_type.startswith('list:'))
     elif field.regex and not field.requires:
         requires.append(validators.IS_REGEX(regex))
diff --git a/gluon/packages/dal b/gluon/packages/dal
index c4ec44ca..b34b8be0 160000
--- a/gluon/packages/dal
+++ b/gluon/packages/dal
@@ -1 +1 @@
-Subproject commit c4ec44cac84c148121af340b27799b1c2f4e76e7
+Subproject commit b34b8be0b54332ff5e87e09ed80ed20b1820b04c