  Polar magnetospheric gaps consume a fraction of the electric potential that
develops accross open field lines. This effect modifies significantly the
structure of the axisymmetric pulsar magnetosphere. We present numerical
stead-state solutions for various values of the gap potential. We show that a
charge starved magnetosphere contains significantly less electric current than
one with freely available electric charges. As a result, electromagnetic
neutron star braking becomes inefficient. We argue that the magnetosphere may
spontaneously rearrange itself to a lower energy configuration through a
dramatic release of electromagnetic field energy and magentic flux. Our results
might be relevant in understanding the recent December 27, 2004 burst observed
in SGR 1806-20.
