Newbee to hibernate using hibernatetool from ant

Hibernate Tools
1

I have reverse engineered using eclipse and hibernatetool plugin , but now want to do the same thing via ant and hibernatetool but getting error
hibernatetool] INFO: HHH000115: Hibernate connection pool size: 1 (min=1)
[hibernatetool] Aug 19, 2021 5:56:31 PM org.hibernate.dialect.Dialect
[hibernatetool] INFO: HHH000400: Using dialect: org.hibernate.dialect.SybaseDialect
[hibernatetool] Aug 19, 2021 5:56:31 PM org.hibernate.engine.jdbc.env.internal.LobCreatorBuilderImpl useContextualLobCreation
[hibernatetool] INFO: HHH000423: Disabling contextual LOB creation as JDBC driver reported JDBC version [3] less than 4
[hibernatetool] Aug 19, 2021 5:57:41 PM org.hibernate.tool.Version
[hibernatetool] INFO: Hibernate Tools 5.2.3.Final
[hibernatetool] An exception occurred while running exporter #2:hbm2hbmxml (Generates a set of hbm.xml files)
[hibernatetool] To get the full stack trace run ant with -verbose
[hibernatetool] java.lang.RuntimeException: java.io.IOException: Server returned HTTP response code: 503 for URL: http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd
[hibernatetool] java.io.IOException: Server returned HTTP response code: 503 for URL: http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd

BUILD FAILED
\build.xml:92: java.lang.RuntimeException: java.io.IOException: Server returned HTTP response code: 503 for URL:

any ideas ?

Jdk 1.8
hibernate 5.2.17

from ant build.xml

       <hibernatetool>
         <jdbcconfiguration
          configurationfile="hibernate.cfg.xml"
          revengfile="hibernate.reveng.xml"
          packagename="${hibernate.packagename}"/>



        <hbm2hbmxml destdir="${src}"/>
        <hbm2java   destdir="${src}"/>

       </hibernatetool>