Problem sorting custom render column

I am new to datatables. I like it so far, but this one thing is currently driving me nuts. Hope somebody can help.

I have a custom render column with prices (prefixed with their currency, eg. "DKK 99.00"). I would really like to sort this column numerically and not alphabetically.

I have added a data-sortattr om the TD but no real luck there.

I have also tried give the column the "type": "num" but that didn't do the trick either. It sorted things correctly ascending ub t the asc/desc toggle stopped working when clicking the column header.

Example can be found here: http://sextoyprices.com/test.php

Any ideas?