[TYPO3-mvc] Autoloader Error when using argument validation in extbase 6.1 controller

[Torsten Schrade]

Hi List,

during the development of an extbase 6.1 plugin i just stumbled over 
the following issue: Using argument validation in the controller throws 
a "1289386765: Could not analyse class: XYZ maybe not loaded or no 
autoloader?" exception but only if the tested argument is not valid. 
Here is the offending action from my controller

/**
 * Search through all objects
*
* @param string $keywords
* @validate $keywords stringLength(minimum=3)
* @return void
*/
public function searchAllAction($keywords) {
}

As soon as a keyword with less than three characters is submitted, the 
controller fatals as described above. Have you also experienced this? 
What could be the reason? Thanks for comments and best regards,

Torsten