The only way I could access the GMX Mediacenter on my Ubuntu Feisty install was by using Konqueror. Nautilus or mount with davfs aborted with errors. This is caused by the buggy/non-standard GMX WebDAV Server. Installing the current Debian unstable package makes access possible.
The developers of davfs2 are kindly trying to include workarounds into their code, but sometimes these get broken between releases. But the current Debian unstable package does work.
I rebuilt the package on Ubuntu 7.04 as described in my hddtemp posting using unmodified Debian sources. You may download the resulting i386 package.
I haven’t done any fine tuning of my setup yet, like automount and user access. But it is indeed working this way for me:
Create mount point
# mkdir /media/webdav-gmx
Add mount commands to /etc/fstab
# gmx mediacenter https://mediacenter.gmx.net/ /media/webdav-gmx davfs user,noauto 0 0
Add login (Customer No. and password) to /etc/davfs2/secrets
# gmx mediacenter https://mediacenter.gmx.net/ 0123456 P455W0rdsRfun
Mount it
# mount /media/webdav-gmx
ChangeLog
[2009-04-26: Fix box.net links.]