Clean installation of OpenERP 7.0 from community backports, with eInvoicing module.
Create a second email template for customer invoice (cloning the existing one).
Create a customer invoice.
Validate the invoice and click the button to send it by email.
Any time you change the email template combobox, OE create a new record ir_attachment.
Is this the correct behaviour or Is this a bug?
PS: openerp.com demo act the same way (you can see that installing knowledge module)