can call SchemaValidator from the Ant script as given below:
<target name="schemavalidate">
<taskdef name="schemavalidator"
classname="org.hibernate.tool.hbm2ddl.SchemaValidatorTask"
classpathref="class.path"/>
<schemavalidator
properties="hibernate.properties">
<fileset dir="src">
<include name="**/*.hbm.xml"/>
</fileset>
</schemavalidator>
</target>