I have the same problem as Simon in this post.
He found out some sort of a solution, but it does not work for me. Please, could someone explain me what is going on in this answer or advice me something else.
PS: there is an example on the asp.net site which doesn't work exactly the same way as my reorder list... (click view a demo)
The solution that is suggested here adds these few lines to web.config:
<add path="ScriptResource.axd" verb="GET,HEAD"
System.Web.Extensions, Version=1.0.61025.0, Culture=neutral,
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