[imp] Attach a copy of your PGP public key to the message?

[ANANT S ATHAVALE]

Dear List,

After upgrade from Horde Groupware WebMail edition from 1.2.3 to 1.2.4, I am getting one additional option to select during composing a new message. 

Attach a copy of your PGP public key to the message?

We do not have any PGP key servers defined.  I do not want this option to be seen during compose.  How can I disable this?

Regards,

Anant Athavale.