Can't use isCrossRef with polymorphic relationships

[lcsdms]

When I try using the following schema to generate crossref methods for a polymorphic relationship, I get this error:
[Symfony\Component\Debug\Exception\FatalThrowableError] Call to a member function getPhpName() on null

• Version used: 2.0.0-alpha7

This is the schema.xml for example:

<?xml version="1.0" encoding="utf-8"?>
<database name="default" defaultIdMethod="native" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:noNamespaceSchemaLocation="vendor/propel/propel/resources/xsd/database.xsd" defaultPhpNamingMethod="underscore">

  <table name="contact" idMethod="native" phpName="Contact">
    <column name="id" phpName="Id" type="INTEGER"  autoIncrement="true" primaryKey="true" required="true"/>
    <column name="name" phpName="Name" type="VARCHAR" size="45"/>
    <vendor type="mysql">
      <parameter name="Engine" value="InnoDB"/>
    </vendor>
  </table>

  <table name="entity_relationship" idMethod="native" isCrossRef="true" phpName="EntityRelationship">
    <column name="entity_id" phpName="EntityId" type="INTEGER" primaryKey="true" required="true"/>
    <column name="entity_type" phpName="EntityType" type="VARCHAR" size="45" />
    <!--Has to be primaryKey to generate getRelationships on model-->
    <column name="relationship_id" phpName="RelationshipId" type="INTEGER" primaryKey="true" required="true"/>
    <foreign-key foreignTable="contact">
      <reference local="entity_id" foreign="id"/>
      <reference local="entity_type" value="USER"/>
    </foreign-key>
    <foreign-key foreignTable="relationship" name="fk_entity_relationship_relationship">
      <reference local="relationship_id" foreign="id"/>
    </foreign-key>
    <index name="fk_entity_relationship_relationship_idx">
      <index-column name="relationship_id"/>
    </index>
    <vendor type="mysql">
      <parameter name="Engine" value="InnoDB"/>
    </vendor>
  </table>

  <table name="relationship" idMethod="native" phpName="Relationship">
    <column name="id" phpName="Id" type="INTEGER" primaryKey="true" required="true" autoIncrement="true"/>
    <column name="name" phpName="Name" type="VARCHAR" size="45"/>
    <column name="type" phpName="Type" type="VARCHAR" size="45"/>
    <vendor type="mysql">
      <parameter name="Engine" value="InnoDB"/>
    </vendor>
  </table>
</database>

[wleona3]

I solved this here: but doesn't look like it's gonna get pulled into propel2: #1319

[lcsdms]

Thanks @wleona3 , I thought that was already supported and it was a bug.