An application sends a ZGM_SETCELLJDATE message to set the specified cell in the ZeeGrid to the date specified by the julian date in lParam.
ZGM_SETCELLJDATE
wParam = (WPARAM)(int) iCellIndex; //Cell index
lParam = (LPARAM)(int) iJulianDate; //julian date
If the julian date specified in lParam is a valid julian date, the message returns TRUE, otherwise FALSE.