Support of ant 1.6+ conditions

[EJ Ciramella]

Is there a newer version of the maven-antrun-plugin?
 
We would like to pass long a true/false property.  If I have:
 
    <condition property="is.preview">
      <istrue property="preview"/>
    </condition>
 
I get this error:
 
Class org.apache.tools.ant.taskdefs.condition.IsTrue doesn't support the
"property" attribute
 
Any suggestions?