Version: 1.7 (using KDE Devel) Installed from: Compiled sources Compiler: gcc-3.4.1 OS: Linux The M- function, i.e. subtracting a value from the memory doesn't work. That's because slotMPlusMinusclicked() first calls EnterEqual() which then subsequently calls UpdateDisplay() which resets the "pushed" state of the "Inv" button and thereby clears the "inverse" flag. Simply removing the EnterEqual() call *seems* to work, but I'm not entirely sure since I don't know what EnterEqual() is actually supposed to do.
Fixed in KCalc 1.8