Microblogging Site

Looking for someone to build a Twitter-like microblogging platform for an online community, subject to the following specs: 1. Based on open source microblogging software (e.g., Identica, Jaiku, Sharetronix). 2. Includes groups, with at least four hierarchical levels. ? For example: ? ? ? ? - Group ? ? ? ? - Subgroup 1 ? ? ? ? - Subgroup 2 ? ? ? ? - Subgroup 3 3. Users should have the ability to create groups at each of these levels. 4. Administrative controls for all aspects of the sites, including the ability to delete posts, users, groups, etc. 5. Easily customizable design (though this may be dependent on which platform you choose). 6. Search and directory functionality, including the ability to search posts, groups, and subgroups. 7. Must be scalable. This is a serious project. ? Please let me have your bids.