Chapter 21.1.1 of the User Guide states:

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<target name="deploy.par">
<taskdef name="deploypar" classname="org.jbpm.ant.DeployProcessTask">
<classpath -make sure the jbpm[version].jar is in this classpath--/>
</taskdef>
<deploypar par="build/myprocess.par" />
</target>

To deploy more process archives at once, use the nested fileset elements. The file attribute itself is optional. Other attributes of the ant task are:

• cfg: cfg is optional, the default value is 'hibernate.cfg.xml'. The hibernate configuration file that contains the jdbc connection properties to the database and the mapping files.
• properties: properties is optional and overwrites all hibernate properties as found in the hibernate.cfg.xml
• createschema: if set to true, the jbpm database schema is created before the processes get deployed.
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http://docs.jboss.org/jbpm/v3.2/userguide/html_single/#theprocessarchive

But this description is old now. This should be:

=============
<target name="deploy.par">
<taskdef name="deploypar" classname="org.jbpm.ant.DeployProcessTask">
<classpath -ensure jbpm[version].jar is in this classpath--/>
</taskdef>
<deploypar process="build/myprocess.par" />
</target>

To deploy more process archives at once, use the nested fileset elements. The process attribute itself is optional. Other attributes of the ant task are:

• jbpmcfg: Optional, the default value is jbpm.cfg.xml. The JBPM configuration file can specify the location of Hibernate configuration file ( the default value is hibernate.cfg.xml ) that contains the jdbc connection properties to the database and the mapping files.
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