[Error][Exception]No shipments built for order bundle

When plan shipment from Order Release, can not built shipments. There are some warning and errors as below:

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2013-07-23 17:04:05.902672317DebugPlanningNo Service Time found during estimation. Removing leg option. [[ACTIVE] ExecuteThread: '14' for queue: 'weblogic.kernel.Default (self-tuning)']
2013-07-23 17:04:05.902672317WarningPlanningAfter estimating service time, 0 leg options are still feasible. [[ACTIVE] ExecuteThread: '14' for queue: 'weblogic.kernel.Default (self-tuning)']
2013-07-23 17:04:05.903672317WarningPlanningNo feasible shipments created for Itinerary: CARGOSMART.OOCL_ROUTE_001. [[ACTIVE] ExecuteThread: '14' for queue: 'weblogic.kernel.Default (self-tuning)']
2013-07-23 17:04:05.961672317ErrorExceptionNo shipments built for order bundle
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Think may due to "After estimating service time, 0 leg options are still feasible", is anyone can help me on this?

My testing PO intends to transport from Hong Kong to Singapore.
And have defined a itinerary that include two "List Legs", one destination location is Hong Kong , and the other is Singapore.
And have assigned "rate offerring" to that two legs.

Any wrong for me ? any one can help?