[TYPO3-mvc] There is more than one plugin that can handle this request

[Christian Essl]

I made 3 Plugins in my extbase Extension, all of them include exactly the same actions like this:
Tx_Extbase_Utility_Extension::configurePlugin(
                                $_EXTKEY,
                                'Lehrgangliste',
                                array(
                                               'Lehrgang' => 'list, show, new, create, edit, update, delete, visibilityShow, visibilityHide',
                                ),
                                // non-cacheable actions
                                array(
                                               'Lehrgang' => 'create, update, delete, visibilityShow, visibilityHide',
                                )
);

Now when I insert either the _first_ or the _third_ plugin from the list, the following error is thrown:

There is more than one plugin that can handle this request (Extension: "Extensionname", Controller: "Lehrgang", action: "show"). Please specify "pluginName" argument

This looks completely arbitrary to me, since only the second plugin from the three seems to work, altough all of them are configured to use the same actions.
As far as I make sense of this error, TYPO3 can't find the plugin and wants me to specify it. But that should not be the case, since I explicitely chose the plugin from the plugin selector in the backend. Do I misunderstand the meaning of this error?

Mit freundlichen Grüßen,

Christian Eßl
Certified TYPO3 Integrator / Mobile Web Developer

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