Maybe there is data missing from your mesh, and it's not uploadable. How long did it take you to determine that it's Linden Labs' fault?
Try reviewing the requirements for mesh uploads, and checking for those in your model. Also, try uploading a simple cube with no complex information like materials on it, but with a UV map. If this doesn't work, then you have a problem, but I doubt it won't since I have had plenty of success uploading complicated meshes with materials, UV maps, over 2000 faces, 4 LOD's from files, and even edge splits.
Try not to insult the creators of a game (world) you enjoy. If you enjoy it, you should be glad they made it, and willing to accept what changes they make to their creation, because they have every right to do with it what they will.