[TYPO3-shop] Problem with mod_rewrite

[Rolf Aglaster]

Dear list,

I have since some month a working shop installation. Now I tried to swap 
to real urls. With the other pages everything works fine. But when I try 
  a single view of my items I get an error message because the link is 
displayed as:

http://www.mydomain.tld/6.0.html>       <font-face=

and this leads to a error 404.

A look at my template didn't help now. Can anyone give me a hint where 
to find the bug?

For information: my shop is running on Vers. 3.7.0 with tt_products 
Vers. 2.2.3.

Does an upgrade to the current shop version help or will I find lots of 
problems with the older configuration?

Thanks for Your hints

Cheers
Rolf