If you need to use the signature for your email templates and you have been upgraded from v13 to v14 you will see that there is a change on that, as the option "Author signature (mass mail only) " (under the tab Email Configuration in the template) is not available in v14.
I have not found another way to activate this option, but if you copy this code ${user.signature | safe} in your email template under Content tab, you will generate your signature every time you send an email using that email template.