Better response handling when receiving 0 messages
Better response handling when receiving 0 messages

- Throw error only on error conditions
- Return empty array of messages when no messages returned

git-svn-id: abaeb2b3ba5a94ed391a9405ad7d63d0414021c9@22984 44c647ce-9c0f-0410-b52a-842ac1e357ba

sandsmedia/zf,grzana12/ZendFramework,grzana12/ZendFramework,sandsmedia/zf,sandsmedia/zf,grzana12/ZendFramework,grzana12/ZendFramework