make release and error while making iso

Hi.

I did a "make release" run on my Computer. All went fine, in the CHROOTDIR=/data/RELEASE is all i need to make some isos of "my" FreeBSD Release. 
(there is a R/cdrom with disc1 and disc2). 
Ok, here is the way i wanted to make in iso, and the error:

asg_at_huibuh:/data/lbsd_de/lbsd_de/src/release:make iso.1 -DMAKE_ISOS
Creating ISO images...
mkisofs: No such file or directory. Invalid node - /R/cdrom/disc1
*** Error code 2

Stop in /data/lbsd_de/lbsd_de/src/release.

So, what does this mean? In my CHROOTDIR is a directory /R/cdrom/disc1...

I appreciate any help.

Thank in adavance.

Axel