Shibboleth breaks Apache error message formatting

[Cantor, Scott]

> Allthough I cannot explain the behaviour of the Service Provider 2.5.1
> together with Apache 2.4.3 I was able to mitigate it by setting
>     ShibDisable On
> to the server root and explicitly setting
>     ShibDisable Off
> to the <Location /Shibboleth.sso> and to our Shibboleth-protected area.

I don't know what it's doing, and I won't have time to look at it anytime soon, but please file a bug.

-- Scott