Array.Add error on Accordion Sample

Hi all !

I've just tried to run the Accordion Sample but i have a problem.

My accordion appears normal and the correct selectedIndex is selected but when i click on other tabs nothing happend.

This is probably because I javascript error. On the page loading I have :

Array.add is not a function
http://localhost:55969/SampleWebSite/WebResource.axd?d=mfyjuyIi_kyiiageb8-dhJuhhEl4d31tjtLnqXaaEJUweLlnyGkeivorEaIgdU-PbZW9-5qoeQV4YUrf2DMON_wD741USQBsSK41MaLx_5k1&t=633001666170937500
Line: 156

Thanks !

Bye

When i look in the webResource.axd the problem is in the initialize : function().

Sounds like maybe the server doesn't have ASP.NET AJAX Beta *2*?