ReturnURL using Forms Authentication

Hello
I'm having trouble with the ReturnUrl property using forms authentication.  If my URL is http://www.mycoolsite.com/login.aspx?ReturnUrl=%2fsearch.aspx, the ReturnURL value in the querystring is ignored and it always sends me to the defaultUrl value default.aspx. 
login.aspx:
FormsAuthentication.RedirectFromLoginPage(txtEmail.Text, chkRememberMe.Checked)
web.config:
  <system.web>
        <authentication mode="Forms">
            <forms loginUrl="login.aspx"
               protection="All"
               timeout="30"
    ...