"Read more" Links on category page with intro does not work

Hello!

I found an issue only appearing on category pages with intro:

The “Read more”-Link (german: “Weiterlesen”) does not work on a category page with intro. It only points back to the current page. These Links are automatically generated by the Theme after 38 words.

When you click on the headline or the post thumbnail everything works fine.

There’s no problem on normal category pages and on the main page.

You can check out here:
http://steyvel.com/category/kirche/wjt-blog-2013/ (The Weiterlesen-Link works)
http://steyvel.com/kirche/wjt-blog-2013/ (The Weiterlesen-Link does not work, but the links an thumbnails and headlines do)

I already deactivated plugins, but nothing changed.

Thank you for your support! 🙂