Add to include file:
<?xml version="1.0" encoding="utf-8"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
<sitecore>
<!-- SCHEDULING -->
<scheduling>
<!-- Agent to publish database periodically -->
<agent type="Sitecore.Tasks.PublishAgent" method="Run" interval="00:02:00">
<param desc="source database">master</param>
<param desc="target database">web</param>
<param desc="mode (full or smart or incremental)">incremental</param>
<param desc="languages">en, fr, de</param>
</agent>
</scheduling>
</sitecore>
</configuration>
language must me exact - ex. french can not be "fr" if it is created in Sitecore as "fr-FR"
If you are patching more than one publishing agent, make sure that the first line og code is different, or the pathcing will overwrite the first.
ex, if you have to publishing agent running, to two different databases, each of them will look like:
<agent type="Sitecore.Tasks.PublishAgent" method="Run" interval="00:02:00">
But change it to
<agent type="Sitecore.Tasks.PublishAgent" method="Run" interval="00:02:00" hint="FirstPublishingAgent">
<agent type="Sitecore.Tasks.PublishAgent" method="Run" interval="00:02:00" hint="SecondPublishingAgent">