Primefaces shows Date with One Day Mismatch

Lately I noticed, that primefaces doesn’t show the correct date. It’s a timezone issue.
You can fix it in the web.xml with

<context-param>
 <param-name>javax.faces.DATETIMECONVERTER_DEFAULT_TIMEZONE_IS_SYSTEM_TIMEZONE</param-name>
 <param-value>true</param-value>
</context-param>

Source: stackoverflow