[TYPO3-linux] Fluid/Extbase error after Installation

[Hendrik]

hi,

on a fresh installation of typo3 6.02 on Lampp 1.8.1 inlcuding PHP Version 5.4.7

i get the following error message as soon as I call the extension manager:

#1237900529: The argument "addCssFiles" was registered with type "array", but is of type "string" in view helper "TYPO3\CMS\Extensionmanager\ViewHelpers\Be\ContainerViewHelper"


any ideas how to handle this?