subfs and dvd/cdrom.

Hi, my dvd and cdrom devices give me an error when I try to mount them, 
"fs type subfs not supported by kernel." 

I built my own kernel with the downloaded suse kernel sources 2.6.5-7.108. 
I used the /proc/config.gz from the original installation to template my 
.config for the new kernel so I shouldn't have changed any functionality. 
However, I can't seem to find an option in the .config file that 
corresponds to this function anyway.

Can anyone help me out? Please.

Thanks,

Michael