Error using Fluid with Microsoft Office 365

[Chris Bloom]

One of my clients just switched from using their own Exchange server
to Microsoft's SaaS product, Office 365. Since then, I can no longer
log in to their webmail service via Fluid though I can in both the
stand alone Firefox and Safari browsers. When attempting to log in
with Fluid I get the following error message:

> Microsoft Online Services is unavailable from this site for one of the following reasons:
> * This site may be experiencing a problem
> * The site may not be a member of the Windows Live Network
>
> You can:
> * You can sign in or sign up at other Microsoft Online Services sites, or try again later at this site.

I found an old thread from 2007 describing the same problem back then
with whatever version of Safari was in use at the time:
http://forums.macrumors.com/showthread.php?t=393065.

Is anyone else experiencing this issue? I've got the whitelist
disabled and cookies set to not shared, but otherwise all of the
default settings are in use. Adjusting the User Agent hasn't had any
effect.