code: @Override
      public void assignVariable(final String variableName, final Object value, final boolean sysgen) throws Exception
      {
          /*
           * Only store supported types in the stack.
           */
          if (value instanceof Date)
              getVariables().put(variableName.toLowerCase(),
                      new Variable(variableName, CalendarFactory.convert((Date) value), sysgen));
          else if (value instanceof Calendar)
              getVariables().put(variableName.toLowerCase(),
                      new Variable(variableName, CalendarFactory.convert((Calendar) value), sysgen));
          else
              getVariables().put(variableName.toLowerCase(),
                      new Variable(variableName, value, sysgen));
      }
docs: {@inheritDoc}