There are something wrong when using inet type with Hibernate

Hi

When I use inet type with hibernate. I mapping as follow:

    <property name="registerIp" type="java.lang.String">

           <column name="`registerIp`" />

       </property>

       <property name="isBlock" type="java.lang.Boolean">

           <column name="`isBlock`" not-null="true" />

    </property>

The  registerIp is inet type,when I insert into the progresql database, it show

org.springframework.orm.hibernate3.HibernateJdbcException: JDBC exception on Hibernate data access; nested exception is org.hibernate.exception.SQLGrammarException: Could not execute JDBC batch update

how can I solve it ,thanks