> root device (default cd0e): cd0d
> dump device (default cd0b): 
> file system (default generic): 
> root on cd0d dumps on cd0b
> no file system for cd0 (dev 0x1203)
> cannot mount root, error = 79

The way the image is made (see src/etc/etc.sparc/Makefile.inc) yields
a somewhat unusual label, but one that's perfectly OK to mount all
filesystems in the image using vnd(4).

I notice, however, that the SCSI cd driver does not bother to read the
actual label from the medium. You could try this:

===================================================================
RCS file: /cvsroot/syssrc/sys/dev/scsipi/cd.c,v
retrieving revision 1.141
diff -r1.141 cd.c
1200a1201
>       char *err;
1204a1206,1210
>       /* Read label from media, if present */
>       err = readdisklabel(MAKEDISKDEV(0, cd->sc_dev.dv_unit, RAW_PART),
>                       cdstrategy, lp, cd->sc_dk.dk_cpulabel);
>       if (err != NULL)
>               printf("just testing: readdisklabel: %s\n", err);