How can I solve these DSL warnings?

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

Remove underscore from name ('_S0D'->'S0D') or just ignore...

Change to And(Local0, 0x0F, Local0). This form will store result of operator back to Local0, probable intention of the statement...

Ignore.

Ignore, or change to 0xFFFF.

Many thanks for your help!! :)

I fixed the warnings, if all works good I'll post the fixed dsdt in the proper acpi website section. I added an useful patch (made my Daniel Drake, a gentoo dev) to fix the annoying LID problem that affects a lot of Dell notebook models: the lcd monitor doesn't come up when the lid is reopened.

Cheers,
Laurento