Notice on every puppet agent run with foreman 1.4.0 and puppet agent 3.4.2

Running Puppet agent on demand …

Notice: Using less secure serialization of reports and query parameters for
compatibility

Notice: with older puppet master. To remove this notice, please upgrade
your master(s)

Notice: to Puppet 3.3 or newer.

Notice: See http://links.puppetlabs.com/deprecate_yaml_on_network for more
information.

How do I fix this?