[TYPO3-commerce] Only backend-user with admin rights can see the products in backend

[Sven Mirkowitz]

hello,

I'm using tx_commerce 0.11.15 and Typo3 4.2.8

I've created a backenduser and gave him all possible module, access 
rights via a group

After login the user can see the commerce-menue, but if he clicks on 
"category" he can't see the products, only the first folder category 
with no content. Also clicking on "orders" shows no result.

After giving him admin-rights he can see everything, but this is not a 
good solution.

Does somebody have a tip or is this a bug?

Sven