Does PMML support probability calibration?
I'm not too familiar with PMML, but probability calibration (or at least, the most well-known methods, Platt scaling and isotonic regression) can be viewed as a stacked ensemble, with the output of your model being fed into a univariate regression model.  PMML appears to support ensembling; see the fourth example at http://dmg.org/pmml/v4-3/MultipleModels.html