VisualTotals + drillthrough throws Exception: cannot cast VisualTotalMember to RolapCalculatedMember (RolapCell.java)

Using VisualTotals, I suddenly was getting errors thrown when trying
to check for drillthrough capability on a cell, although for leaf
cells this should be possible. (class cast exception - cannot cast
VisualTotalMember to RolapCalculatedMember) in RolapCell.java.

proposed change (fix) [RolapCell.java - in replaceTrivialCalcMember() ]:

RolapCalculatedMember measure = (RolapCalculatedMember) member;
final Exp expr = measure.getFormula().getExpression();
to:

final Exp expr;
if (member instanceof VisualTotalMember)

{ VisualTotalMember vtMember = (VisualTotalMember)member; expr = vtMember.getExpression(); }

else

{ RolapCalculatedMember measure = (RolapCalculatedMember) member; expr = measure.getFormula().getExpression(); }

From what I can see in the perforce repo, this problem should apply to the most recent versions too.