to do that you have several options:
- assign task to a group where you have many users that can claim and then work on the task
- use delegate operation on taskClient
- use forward operation on taskClient
personally I would recommend the first approach as it's the easiest one and clear to everyone. Once task was claimed by a person that is on vacation such task can be released by administrator and by that will be available for another user from the group to work on it
HTH