Search web parts conflict with AjaxControlToolkit

Hi

I have enabled "Show Query Suggestion" for a Search web part on a page that has a custom web part that uses AjaxControlToolkit.

The tabs for the custom web part which depends on the AjaxControlToolkit are not displayed and the console of my browser has the error pasted below:

Part of the source for above is also pasted below:

However, if I disable i.e. un-check "Show Query Suggestion" in the Search web part the custom web part displays properly.

Has anybody experience this and/or is there is any one that can guide on how to troubleshoot this and find a solution.

Thanks

SO

Edit:

It would seems that "ShowQuerySuggestion" will cause a js to be emitted onto the page and the js emitted is /_layout/ajaxtoolkit.js from SharePoint 2010 14 hive.  When this is case, the errors below appears in the browser developer console

Any help on where these two classes are located will be appreciated.