iCAL attachment

Hello,

I’d like to send an email with iCAL invitation. Does enyone tested this? How to do that? For send email I useing this but I have no idea how to declare attachments like iCAL.

Command_SYS.Mail(sender_,
                   from_, 
                   to_list_,
                   cc_list_,
                   bcc_list_,
                   subject_,
                   text_,
                   attachments_,
                   mail_sender_ 
                   );

Best Regards

Bartosz.