Opening the login-page with iexplorer 9 doesn t work her.
The Sophos logo appears and that is all. No login and no password field.
Ralf
Did you try a forced (Shift-) reload? We've occasionally seen caching problems with some browsers.
In general, we've tested the webadmin with IE9 and have seen no major problems yet.
With IE9, I've seen this when Compatibility View is enabled for WebAdmin. Try disabling CV.