Mailboxes should have been implemented during the last major patch on OB. Don't know why it wasn't..
But yes, there should be a way to do that.
Yes, the last patch in OB introduced mailboxes. They don't look like mailboxes (they look like high-tech consoles), and they're right next to the bank consoles. Your character will have to be physically present at a mailbox to send or receive items. Also, I don't believe transfer of items is limited to characters on the same account, although I haven't tested this so I can't say for sure.