C# webbrowser Ajax call

C# webbrowser Ajax call

I am using a webbrowser control embeded in C# WPF .NET4 app. Whenever I
press manually the button in a form, the browser hangs on "Your request is
being processed" message and nothing happens. If I do the same in full IE
browser the page is processed normally producing the results. What I am
missing? Thanks The code behind the button is the following
<a onclick="startSearch();" href="javascript:void(-1);" name="btnNext"
class="btn floatLe noClear btnSubmit btnRight">
<span>Continue</span>
</a>