Hitachi TD61-2472 - Manual (Page 33)

5 To delete a send message, select that message, press the LeftSoft key to
select the sub-menu, then select "3. Delete".
The screen in the figure on the right (3rd line) is displayed.
Select whether or not to delete with the keys, then press the key to
finalize the deletion.
1.8.5 Delete All
Deleting all the messages from the Inbox, drafts, and Outbox.
1 From the IM menu, select "5. Delete all".
Hitachi Cable 29