Antelope has an additional task called repeat which can be used like this:
<taskdef name="repeat" classname="ise.antelope.tasks.Repeat"/>
<repeat count="2" interval="1" unit="milliseconds">
<echo>${count}</echo>
</repeat>
Also found this solution from another question:
<target name="example4">
<property name="n" value="3300"/>
<property name="target" value="callee"/>
<property name="param" value="calleeparam"/>
<script language="javascript">
// does n antcall's with iteration number param
var n = parseInt(project.getProperty("n"),10);
for (var i = 0; i < n; i++) {
var t = project.createTask("antcall");
t.setTarget(project.getProperty("target"));
var p = t.createParam();
p.setName(project.getProperty("param"));
p.setValue(""+i);
t.perform();
}
</script>
</target>