  We compute, to two loops in pertubation theory, the fermionic contribution to
rectangular RxT Wilson loops, for different values of R and T.
  We use the overlap fermionic action. We also employ the clover action, for
comparison with existing results in the literature.
  In the limit R, T -> Infinity our results lead to the shift in the b-quark
mass. We also evaluate the perturbative static potential as T -> Infinity.
