Bluetooth enables portable electronic devices to communicate wire-lessly via short-range ad-hoc networks. Initially Bluetooth will be used as a replacement for point-to-(multi)point cables. However, in due course, there will be a need for forming multihop ad-hoc networks over Bluetooth, referred to as scatternets. This paper investigates the capacity assignment problem in Bluetooth scatternets. The problem arises primarily from the special characteristics of the network and its solution requires new protocols. We formulate it as a problem of minimizing a convex function over a polytope contained in the matching polytope. Then, we develop an optimal algorithm which is similar to the well-known flow deviation algorithm and that calls for solving a maximum-weight matching problem at each iteration. Finally, a heuristic algorithm with a relatively low complexity is developed.