How can I solve these DSL warnings?

[Frittella Laurento <laurento.frittella@gmail.com>]

Hi all,
I'm trying to fix these warnings that appears during dsl compile:

  dsdt.dsl  2341:                 Method (_S0D, 0, NotSerialized)
  Warning  1097 -      Unknown reserved name ^  (_S0D)

Code (part of interest):
  Method (_S0D, 0, NotSerialized)
  {
      Store (SMI (0x85, 0x00), Local0)
      And (Local0, 0x01, Local0)
      If (LEqual (Local0, 0x00))
      {
        Return (0x03)
      }
      Else
      {
        Return (0x00)
      }
  }


The other kind of warning is:

  dsdt.dsl  3040:                         And (Local0, 0x0F)
  Warning  1104 -                                   ^ Result is not
used, operator has no effect

Code (part of interest):
  If (LLess (Local0, 0x80))
  {
    And (Local0, 0x0F)
    Store (0x01, Local1)
    ShiftLeft (Local1, Local0, Local1)
    Store (Local1, IRA)
  }


Another one:
  dsdt.dsl  3818:                     Return (Package (0x00) {})
  Remark   5070 -    Effective AML package length is zero ^

  Method (_DOD, 0, NotSerialized)
  {
     Return (Package (0x00) {})
  }

The last ;)
  dsdt.dsl  4044:                             Wait (EJTD, 0xA000)
  Warning  1103 -         Possible operator timeout is ignored ^

  Method (_EJ0, 1, NotSerialized)
  {
    Store (SMI (0x87, 0x00), MIS7)
    If (MIS7)
    {
      SMI (0xA6, 0x02)
      SMI (0x49, 0x01)
      Wait (EJTD, 0xA000)
      SMI (0x49, 0x00)
    }

    Return (0x00)
  }


I searched for them on the acpi website but I haven't find these warning
codes.

Regards,
Laurento