Get UniqueID instead of ID from linkbutton

<asp:LinkButton ID="lnkDelete" 
runat="server" Style="cursor: pointer; text-decoration: none;"
OnClientClick="javascript:return confirmMessage(this.UniqueID);" CssClass="buttonfont" Text="Edit" OnClick="lnkDelete_Click">Delete</asp:LinkButton>

function confirmMessage(obj) {
           debugger;
           $("#dialog-confirm").dialog({
               autoOpen: false,
               resizable: false,
               height: 140,
               modal: true,
               buttons: {
                   "Delete": function () {
                       debugger;
                       $(this).dialog("close");
                       __doPostBack('ctl00$ContentPlaceHolder1$JobsRightControl$lnkDelete','');
                       return true;

                   },
                   "Cancel": function () {
                       debugger;
                       $(this).dialog("close");
                   }
               }
           });
           $('#dialog-confirm').dialog('open');
           return false;
       }