[TYPO3-shop] tt_products 2.7.0 Fileextension 'jpg/pdf' not allowed

[cool_coders at web.de]

Hi List
When I create a product with an image or a pdf it appears following error
"Fileextension 'jpg/pdf' not allowed"

Settings under BE/Configurations looks correct
$TYPO3_CONF_VARS['GFX']['imagefile_ext'] = 
'gif,jpg,jpeg,tif,bmp,pcx,tga,png,pdf,ai';

For test purposes i have changed the allowed value for image in tca.php
'allowed' => $GLOBALS['TYPO3_CONF_VARS']['GFX']['imagefile_ext'],
to
'allowed' => 'gif,jpg,jpeg,pdf',
but nothing changes

Hope you can help

THX
Niels Tiedt