Use unique identifier as reference for asynchronous service execution.

git-svn-id: http://svn.zoo-project.org/svn/trunk@514 4b6b6ad6-68b3-4dcc-9231-bd9b83bc5dc3
Use the _getStatus function to use unique identifier and free the allocated memory.

git-svn-id: http://svn.zoo-project.org/svn/trunk@515 4b6b6ad6-68b3-4dcc-9231-bd9b83bc5dc3