you can email me at joe dot audette at g mail dot com
I'll see if it remembers me. But if it does not, it is most likely some IIS configuration has changed on your installation, mojoPortal is trying to set an authentication cookie. The IIS authentication type should be set to have anonymous and windows authentication checked. And the mojoPortal Web.config should be configured for forms authentication which it is by default unless someone has modified the web.config
If it can't set a cookie due to browser settings or is not setting one due to IIS configuration that is what will cause this symptom, but the code in mojoPortal has not changed, it is trying to set a cookie when you use the login page.
Hope it helps,
Joe