There's an extraneous trailing do in the URL.
This is the correct one:
http://48months.tweakker.com/choose/SonyEricsson/XPERIA%20Ray
If that doesn't work then follow the instructions here:
http://community.48months.ie/t5/Need-Help/internet-on-my-phone/m-p/31369#M10212
Hope this helps.
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