We use the "Send via Email" button on the Invoice form to send the invoice to the customer. We have modified the email template for that purpose. The "Add user-signature" field on the template is unchecked, as we send every customer the same email. Also, the "Portal" modules have been uninstalled completely (although we did some testing with the modules before).

Now, for some reason which we were unable to determine every email gets attached two extra fields at the bottom. First the User-signature which is followed by the following line:

Send by <<companyname>> using OpenERP.

Where <<companyname>> is the actual name of our company. Both <<companyname>> and OpenERP are hyperlinks in HTML-formatted messages. We've been looking through the configuration as well as the source code to find where these parts are added to the email message, but haven't found it yet.

Questions:

1. Why is the User-signature added alhough the corresponding flag is unchecked?
2. Which business object is responsible for adding the User-signature (email_template, mail_mail, ir_mail_server)?
3. Where does the Send by <<companyname>> line come from (source code, translations, database, configuration)?