Textbox value get duplicate onblur (google chrome)

[Manuel]

I have this issue. I am using rad ajax manager on a page and also it has textboxes.

every time that part of the page callback or make asynchronous calls to the database. its value got duplicated.

I am using telerik 2010.3.1317.35

Here is the layout

<asp:Content ID="Content1" ContentPlaceHolderID="c" runat="server">
 <telerik:RadAjaxManager ID="RadAjaxManager1" runat="server" OnAjaxRequest="RadAjaxManager1_AjaxRequest"
        UpdatePanelsRenderMode="Inline" ClientEvents-OnRequestStart="ClearNameMsg">

 <AjaxSettings>
            <telerik:AjaxSetting AjaxControlID="RadAjaxManager1">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="subdomainWrapper" LoadingPanelID="CtrlLoadingPnl"
                        UpdatePanelRenderMode="Inline" />
                    <telerik:AjaxUpdatedControl ControlID="DateRg" />                 
                    
                    <telerik:AjaxUpdatedControl ControlID="customDomainWrapper" LoadingPanelID="CtrlLoadingPnl"
                        UpdatePanelRenderMode="Inline" />                    
                </UpdatedControls>
            </telerik:AjaxSetting>
         
  </telerik:RadAjaxManager>

     <div id="subdomainWrapper" runat="server">
                <label>Default Domain</label>
                <ajaxToolkit:FilteredTextBoxExtender ID="EventNameUrlFilter" runat="server" TargetControlID="SubDomainTxt" FilterType="LowercaseLetters,UppercaseLetters,Numbers"></ajaxToolkit:FilteredTextBoxExtender>
                <div class="wrap">
                    <span>http://</span>
                    <asp:TextBox ID="SubDomainTxt" runat="server" ValidationGroup="DefineEventStep1" MaxLength="15"
                        OnBlur="ValidateUrl()" OnKeyPress="UrlKeyPress()" CssClass="http-input" TabIndex="2"></asp:TextBox>
                    <span>.eventsnap.com.sg</span>
                </div>            
            </div>

scripts here
   function ValidateUrl() {
                  if (typeof (Page_Validators) == "undefined") return;
                  var reqVal = document.getElementById("<%=SubDomainRFV.ClientID %>");
                  var regVal = document.getElementById("<%=SubDomainTxtREV.ClientID %>");
                  var urlMsg = "<%=SubDomainValidateStatusLbl.ClientID %>";

                  ValidatorValidate(reqVal);
                  if (!reqVal.isvalid) {
                      cleanStatusMsg(urlMsg);
                      return;
                  }
                  ValidatorValidate(regVal);
                  if (!regVal.isvalid) {
                      cleanStatusMsg(urlMsg);
                      var UrlTxt = document.getElementById("<%=SubDomainTxt.ClientID %>");
                      UrlTxt.style.color = "Red";
                      return;
                  }
                  var ajaxManager = $find("<%= RadAjaxManager1.ClientID %>");
                  ajaxManager.ajaxRequest('SubDomain');
                  return false;
              }

Code behind
   protected void RadAjaxManager1_AjaxRequest(object sender, Telerik.Web.UI.AjaxRequestEventArgs e)
       {
     }


any thoughts on this.

Thanks