diff --git a/libraries/chain/include/graphene/chain/protocol/ext.hpp b/libraries/chain/include/graphene/chain/protocol/ext.hpp
index fda4feee..366dcd63 100644
--- a/libraries/chain/include/graphene/chain/protocol/ext.hpp
+++ b/libraries/chain/include/graphene/chain/protocol/ext.hpp
@@ -168,6 +168,14 @@ struct graphene_extension_from_variant_visitor
 template< typename T >
 void from_variant( const fc::variant& var, graphene::chain::extension<T>& value )
 {
+   if( var.is_null() )
+      return;
+   if( var.is_array() )
+   {
+      FC_ASSERT( var.size() == 0 );
+      return;
+   }
+
    graphene_extension_from_variant_visitor<T> vtor( var.get_object(), value.value );
    fc::reflector<T>::visit( vtor );
    FC_ASSERT( vtor.count_left == 0 );    // unrecognized extension throws here