Weird SCSI messages

[Wim Vandeputte <wvdputte_(_at_)_reptile_(_dot_)_rug_(_dot_)_ac_(_dot_)_be>]

I hooked up an old SONY CDROM to my OpenBSD i386 machine and I got these 
messages:

aha0 at isa0 port 0x330-0x333 irq 9 drq 5: model AHA-1542CP, firmware D.0
aha0: unlocking mailbox interface
aha0: async, parity
scsibus0 at aha0: 8 targets

[snip]

cd1 at scsibus0 targ 5 lun 0: <SONY, CD-ROM CDU-561, 1.7X> SCSI2 5/cdrom removable
probe(aha0:5:1): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:2): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:3): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:4): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:5): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:6): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB
probe(aha0:5:7): Check Condition on opcode 12
    SENSE KEY: Illegal Request
     ASC/ASCQ: Illegal Field in CDB

I didn't have to time to actually test the drive, but the harddisks on 
the bus are working fine. I'm just curious what the messages mean.