[rules-users] Why a split node constraint always is true.

Fllow rule flow split node toNodeId=2 always is true.Please help me. <process > <header> <imports> <import name="t2.state.User"/> </imports> <variables> <variable name="user" > <type name="org.drools.process.core.datatype.impl.type.ObjectDataType" className="User" /> </variable> </variables> </header> <nodes> <start id="1" name="Start"/> <join id="2" name="Restart" type="2"/> <actionNode id="3" name="changeAge"> <action type="expression" dialect="mvel">System.out.println("age: "+user.age);System.in.read();user.age+=1;</action> </actionNode> <split id="4" name="decide" type="2"> <constraints> <constraint toNodeId="2" toType="DROOLS_DEFAULT" name="go to rest" type="rule" priority="1" dialect="mvel">User(age &lt; 3)</constraint> <constraint toNodeId="100" toType="DROOLS_DEFAULT" name="go to end" type="rule" priority="2" dialect="mvel">eval(true)</constraint> </constraints> </split> <end id="100" name="End"/> </nodes> <connections> <connection from="1" to="2"/> <connection from="2" to="3"/> <connection from="3" to="4"/> <connection from="4" to="2"/> <connection from="4" to="100"/> </connections> </process> liuzhikun 2009-10-30