Heya mate, i had the same problem, but mine snapped after three days riding.
Fortunatley i had an old echo hub, and i swapped the axles around and it worked fine. If you can, take the sealed bearings and the axle out, and use one out of another echo hub.
Here is the cheapest echo hub iv seen so far, saves you having to rebuild your wheel
http://cgi.ebay.co.uk/Echo-fixed-rear-hub-...1QQcmdZViewItem
Hope this helps , Tom