solaris handle cdroms with the same ids like harddisks, so you will find your cdrom in /dev/dsk/ with c*t*d*s*. if you know the bus-id, you can mount it with that target id and slice 0.
an easy way to see which of this devices is a cdrom, you can have a look at your device classes in the io management with iostat
for example on my mashine:
root@blade # uname -a
SunOS blade 5.10 Generic_118822-02 sun4u sparc SUNW,Sun-Blade-1000
root@blade # iostat -En
c2t6d0 Soft Errors: 1 Hard Errors: 0 Transport Errors: 0
Vendor: TOSHIBA Product: DVD-ROM SD-M1401 Revision: 1007 Serial No:
Size: 0.00GB <0 bytes>
Media Error: 0 Device Not Ready: 0 No Device: 0 Recoverable: 0
Illegal Request: 1 Predictive Failure Analysis: 0
c1t2d0 Soft Errors: 0 Hard Errors: 0 Transport Errors: 0
Vendor: HITACHI Product: DK32EJ72FSUN72G Revision: 2Q09 Serial No: 0309W0V**0
Size: 73.40GB <73400057856 bytes>
Media Error: 0 Device Not Ready: 0 No Device: 0 Recoverable: 0
Illegal Request: 0 Predictive Failure Analysis: 0
c1t1d0 Soft Errors: 0 Hard Errors: 0 Transport Errors: 0
Vendor: HITACHI Product: DK32EJ72FSUN72G Revision: 2Q09 Serial No: 0309W0V**8
Size: 73.40GB <73400057856 bytes>
Media Error: 0 Device Not Ready: 0 No Device: 0 Recoverable: 0
Illegal Request: 0 Predictive Failure Analysis: 0

you see? one device is called a DVD-ROM and you can see the vendor. first thing on each output for each device is the device-id. so mine would be c2t6d0.....

to mount it type:
mount -F hsfs -o ro /dev/dsk/c2t6d0s0 /directory

greetings PRESSY