@@ -0,0 +1,296 @@
+package org.drools.core.base;%0A%0Aimport org.drools.core.RuntimeDroolsException;%0A%0Apublic class UndefinedCalendarExcption extends RuntimeDroolsException %7B%0A%0A    public UndefinedCalendarExcption(String name) %7B%0A        super(%22No calendar named '%22 + name + %22' has been defined on this session%22);%0A    %7D%0A%7D%0A

throw a meaningful runtime exception when a rule uses a calender not defined on the session