(Open)Solaris: Getting the serial number of the motherboard?

pascal@pgt02:~# smbios -t SMB_TYPE_BASEBOARD
ID    SIZE TYPE
2     202  SMB_TYPE_BASEBOARD (base board)

  Manufacturer: Sun Microsystems
  Product: Sun Fire X4200 M2                     
  Version: To Be Filled By O.E.M.          
  Serial Number: 1005LCB-0807GB0U08              
  Asset Tag: To Be Filled By O.E.M.          
  Location Tag: To Be Filled By O.E.M.          

  Chassis: 3
  Flags: 0x9
        SMB_BBFL_MOTHERBOARD (board is a motherboard)
        SMB_BBFL_REPLACABLE (board is field-replacable)
  Board Type: 0xa (motherboard)