The URL should be working fine. Make sure that you have the System - SEF plugin enabled and that "Allow UTF-8 characters in URL" option is enabled in JoomSEF's Configuration on the Advanced tab.
If you would like us to check the problem directly on your server, please purchase 1 hour of our support time at:
www.artio.net/e-shop/support-services/joomla-related-support-1h
and contact me at
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with your order number and access credentials to your website's administration area and FTP.