Using my IE8 (WinXP, SP3) I can log in when I hover the mouse over the "Sign in" link in the top right corner and fill out the pop-up login form. But if I click on the "Sign in" link and try to log in from the "Member Log-on" page, I get the hamster error just as on my phone.
Unfortunately I don't know how to get the "hover log in form" to stay open when I use my phone.
After reading the post from H.Brydon above, I tried clearing the cookies on my phone and using relaxed settings (accept all cookies, do not send "Do not track request to websites"), but it still fails.
"When you don't know what you're doing it's best to do it quickly" - Jase #DuckDynasty