error when check box is placed in accordianpane

[jamshed ahmed]

function Validations()
	{
if(document.getElementById("chkHomePhone").checked==true && document.getElementById("drpPhoneList").value=="Select Phone Line")
	{
	alert("PLEASE SELECT PONE LINE..");
	return false;
	}


<cc1:Accordion ID="Accordion2" runat="server" SelectedIndex="0" 
        TransitionDuration="300" FadeTransitions="true" 
        style="position:absolute; top: 1417px; left: 307px; height: 136px;">
        <Panes>
        <cc1:AccordionPane runat="server">
        <Header>SINGLE PRODUCT</Header>
        <Content>
        
    <table bgcolor="#E4D7D1">
        <tr>
            <td class="heading" colspan="4">
        Single Product
        </td>
        </tr>
        <tr>
            <td class="text">
                <asp:RadioButton ID="chkHomePhone" runat="server" Text="Home Phone" 
                    GroupName="Category" />
            </td>
            <td class="text">
                <asp:RadioButton ID="chkInterNet" runat="server" Text="Inter Net" 
                    GroupName="Category" />
            </td>
            <td class="text">
                <asp:RadioButton ID="chkTv" runat="server" Text="Television" 
                    GroupName="Category" />
            </td>
        </tr>
        </table>
        </Content>
        </cc1:AccordionPane>
         
         <cc1:AccordionPane ID="AccordionPane3" runat="server">
        <Header>BUNDLE</Header>
        <Content>
        
        <table>
        <tr>
            <td class="heading" colspan="4">
                Bundle 
            </td>
        </tr>
        <tr>
         <td style="white-space:nowrap" class="text">
            <asp:RadioButton ID="rdoHomePhoneNet" runat="server" GroupName="Bundle" Text="Home Phone & InterNet" />
            </td>
            
            <td style="white-space:nowrap" class="text">
            <asp:RadioButton ID="rdoHomePhoneRdoTv" runat="server" GroupName="Bundle" Text="Home Phone & TV" />
            </td>
            
             <td style="white-space:nowrap" class="text">
            <asp:RadioButton ID="rdoNetTv" runat="server" GroupName="Bundle" Text="InterNet & TV" />
            </td>

             <td style="white-space:nowrap" class="text">
            <asp:RadioButton ID="rdoTvHomeNet" runat="server" GroupName="Bundle" Text="Home Phone & InterNet & TV " />
            </td>
        </tr>
                       
    </table>
    </Content>
     </cc1:AccordionPane>
        
    </Panes>
        </cc1:Accordion>




<asp:Button ID="btnAdd" runat="server" Text="ADD" OnClientClick="return Validations()"
                    OnClick="btnAdd_Click" class="button"/>

when this checkbox is placd out of accordian then it works fine but when it is placed withing accordiance pane there is error says object is required