This note addresses the problem of position control of mobile manipulators operating in the task space with state constraints. A relatively simple class of task space regulators consisting of a generalized transpose Jacobian controller with a nonlinear quasi-velocity term, an integral term including a function of manipulator coordinates and the task error plus the gradient of a kinematic criterion function, is proposed. The Lyapunov stability theory is used to derive the control scheme. Through the use of the gradient of the criterion function, an optimal solution to the mobile manipulator task is ensured. The performance of the proposed control strategy is illustrated through computer simulations for a mobile manipulator operating in a three-dimensional task space.