Web Forms :: Links On Masterpage Don't Work?

I have a series of LinkButtons on my masterpage as follows:

<div id="mainNav" runat="server" class="mainnavigation">
<ul>
<li>
<asp:LinkButton ID="lnkHome"

[Code].....

I have simple click events defined for them, like this:

protected void lnkReports_Click(object sender, EventArgs e)
{
Response.Redirect("~/Administrators/Reports.aspx");
}

On any page that uses this masterpage, whether it is in a subfolder or directly at root level with the masterpage, these links don't work in any browser I have except for IE (Firefox, Chrome, Opera, and Safari). By that, I mean:

1. When I mouse over them, the cursor doesn't change to a hand.

2. When I click, nothing happens visually.

3. When I click, nothing happens in code. i.e., I set a breakpoint on the click events for the buttons, and they don't get hit.

In IE, everything works as it should.

In addition, I have subnavigation on some of my child pages, implemented the same way, and it works for all browsers.

<div id="mainNav" runat="server">