[NTG-context] MathML (mkiv) accent shifted to the left

Hi all. I am reasonably sure that in mkii this overbar accent was placed correctly, but in mkiv it is shifted to the left. Any ideas on how to fix it? MWE: \usemodule[mathml] \starttext This \xmlprocessdata{}{<imath><math xmlns=' http://www.w3.org/1998/Math/MathML'><mover accent="true"><mi>p</mi><mo>‾</mo></mover></math></imath>}{} isn't right. \stoptext Many thanks, Duncan