Vm pagination broken with SEF

[Tim Zuidgeest]

Dear Virtuemart users

I'm having a problem with my pagination, and I cannot seem to fix it..
The problem is as follows:
When you go a product category you see the normal first page (with the first product you should see).
When you go to page 2 however, you cannot return to page one. The 1 and the 'previous page' button, don't work as they should, but instead they both function as the 'next page' button.. (thus going to page 3).
This only happens when my SEF urls are turned on. I'm now working with sef404, but the problem also existed with the integrated sef.
You can view the problem here: (this is the good first page)
http://www.fish24shop.nl/view/category/virtuemart_category_id/72.html

Thank you for your help!

Best,

Tim