trouble with breadcrumbs modul

We have recently (2.5 joomla) taken over our club's website on a joomla 3.0 installation, all articles, categories, etc. are imported.

While in the old installation the breadcrumbs module is working properly, it behaves under joomla 3.0 strange: If you click on the read-more-Button in an article that category will appear on the article page in the breadcrumbs line twice - see Attachment.
If you click on the right of the duplicate entries, you land on a category blog page, which probably generated automatically.

I have tried different breadcrumbs modules, all do the same. Also have never found something. Does anyone advice?

To find alternative 3rd party breadcrumbs module