Agent Manager service is not starting (4259112)

The Foglight Agent Manager (FglAM) is installed on a Windows machine as a service. When trying to start up the FglAM, it is failing.

When starting via commandline with debug option the following error comes up:

2013-09-11 15:38:55.889 ERROR [Startup Thread] com.quest.glue.common.util. MessageValidationHandler - An error was encountered while validating the XML structure: unexpected element (uri:"urn:X-quest.com:glue/config/1.5", local:"documentation"). Expected elements are (none) at line 345 [345,31].
  Parsing cannot continue.

Unclosed tag in the config file fglam.config.xml - in this case a documentation tag in line 345:

[...]
<config:time-sync max-allowed-variation="300000">
=>  <config:documentation>
    <config:documentation>
[...]
    </config:documentation>
[...]