Description of problem:
$Summary

Version-Release number of selected component (if applicable):
Version: 4.6.0-SNAPSHOT
Build Number: 73a33d5

How reproducible:
Always

Steps to Reproduce:
1. schedule some operation using following cron expression: 4 2 5

  
Actual results:
Globally uncaught exception:
java.lang.RuntimeException:Failed to add ResourceOperationSchedule: resource=[Resource[id=11145, uuid=9d643d1f-9477-4208-9bc6-eb4df3d73903, type={RHQAgent}RHQ Agent, key=last-rhq-fbrychta.bc.jonqe.lab.eng.bos.redhat.com RHQ Agent, name=RHQ Agent, version=4.6.0-SNAPSHOT]],job-name=[null], job-group=[null], operation-name=[executeAvailabilityScan], subject=[Subject[id=2,name=rhqadmin]], description=[null]
   java.lang.RuntimeException:[1360316857878] javax.ejb.EJBException:java.lang.RuntimeException: java.text.ParseException: Unexpected end of expression. -> java.lang.RuntimeException:java.text.ParseException: Unexpected end of expression. -> java.text.ParseException:Unexpected end of expression.
--- STACK TRACE FOLLOWS ---
Failed to add ResourceOperationSchedule: resource=[Resource[id=11145, uuid=9d643d1f-9477-4208-9bc6-eb4df3d73903, type={RHQAgent}RHQ Agent, key=last-rhq-fbrychta.bc.jonqe.lab.eng.bos.redhat.com RHQ Agent, name=RHQ Agent, version=4.6.0-SNAPSHOT]],job-name=[null], job-group=[null], operation-name=[executeAvailabilityScan], subject=[Subject[id=2,name=rhqadmin]], description=[null]
   at Unknown.Throwable_2(Unknown Source)
   at Unknown.RuntimeException_2(Unknown Source)
   at Unknown.$onFailure_48(Unknown Source)
   at Unknown.onFailure_402(Unknown Source)
   at Unknown.$onResponseReceived(Unknown Source)
   at Unknown.onResponseReceived_6(Unknown Source)
   at Unknown.$fireOnResponseReceived(Unknown Source)
   at Unknown.onReadyStateChange_0(Unknown Source)
   at Unknown.this$static.onreadystatechange<(Unknown Source)
   at Unknown.apply(Unknown Source)
   at Unknown.entry0(Unknown Source)
   at Unknown.anonymous(Unknown Source)
   at Unknown.anonymous(Unknown Source)
Caused by: java.lang.RuntimeException: [1360316857878] javax.ejb.EJBException:java.lang.RuntimeException: java.text.ParseException: Unexpected end of expression. -> java.lang.RuntimeException:java.text.ParseException: Unexpected end of expression. -> java.text.ParseException:Unexpected end of expression.
   at Unknown.RuntimeException_0(Unknown Source)
   at Unknown.instantiate_32(Unknown Source)
   at Unknown.$instantiate_0(Unknown Source)
   at Unknown.$instantiate(Unknown Source)
   at Unknown.$readObject(Unknown Source)
   at Unknown.$onResponseReceived(Unknown Source)
   at Unknown.onResponseReceived_6(Unknown Source)
   at Unknown.$fireOnResponseReceived(Unknown Source)
   at Unknown.onReadyStateChange_0(Unknown Source)
   at Unknown.this$static.onreadystatechange<(Unknown Source)
   at Unknown.apply(Unknown Source)
   at Unknown.entry0(Unknown Source)
   at Unknown.anonymous(Unknown Source)
   at Unknown.anonymous(Unknown Source)

Expected results:
Clear validation error

Additional info:
Another cron exception to test: 0 15 d ? * *