code: public void setTo(Object to) throws ApplicationException {
  	if (StringUtil.isEmpty(to)) return;
  	try {
  	    smtp.addTo(to);
  	}
  	catch (Exception e) {
  	    throw new ApplicationException("attribute [to] of the tag [mail] is invalid", e.getMessage());
  	}
      }
docs: set the value to The name of the e-mail message recipient.
  
  @param strTo value to set
  @throws ApplicationException