precise32:~$ sudo add-apt-repository ppa:avsm/ppa
You are about to add the following PPA to your system:
 Latest stable versions of OCaml and OPAM.
 More info: https://launchpad.net/~avsm/+archive/ppa
Press [ENTER] to continue or ctrl-c to cancel adding it


gpg: keyring `/tmp/tmpU270CK/secring.gpg' created
gpg: keyring `/tmp/tmpU270CK/pubring.gpg' created
gpg: requesting key 61707B09 from hkp server keyserver.ubuntu.com
gpg: /tmp/tmpU270CK/trustdb.gpg: trustdb created
gpg: key 61707B09: public key "Launchpad PPA for Anil Madhavapeddy" imported
gpg: Total number processed: 1
gpg:               imported: 1  (RSA: 1)
OK