[MM3-users] two signatures on sent mail?

Hi, I am a very non-savvy mailman list user. I am trying to set up a list via cPanel but when I send emails there are two signatures. One is my usual signature and the other, below, is appended by Mailman and includes an http link to a non-existent page on my website. How do I strip the auto signature, just leaving my own?

I use Mailman via cPanel on two separate hosting accounts. One works fine and this new one attaches the list address. I can't see what I did differently with the first!

any help gratefully received

Kate