[Grml] root-FS readonly after grml2hd

I just installed latest grml64 sid vi grml2hd and after rebooting from disk /-filesystem ist mounted readonly. Tried it with several combinations of filesystem and bootloader but always the same effect.

Any ideas? The boot-option in /etc/fstab says error=remount-ro but there are no errors in dmesg with the harddisk.

Tobias