ALTER PROCEDURE temp1
	@nam varchar( 50 ), 
            @zap int OUTPUT
as
	insert into temptable (Name) values (@nam)
	select @zap = @@identity

Sub test()
Dim cnn As ADODB.Connection
Dim cmd As ADODB.Command
Dim prm As ADODB.Parameter
Dim varrecs As Long

Set cmd = New ADODB.Command
Set cnn = CurrentProject.Connection

cmd.ActiveConnection = cnn
cmd.CommandText = "temp1"
cmd.CommandType = adCmdStoredProc
Set prm = cmd.CreateParameter("nam", adVarChar, adParamInput,  50 , "Вася")
cmd.Parameters.Append prm
Set prm = cmd.CreateParameter("zap", adBigInt, adParamOutput)
cmd.Parameters.Append prm
cmd.Execute varrecs, adExecuteNoRecords
Debug.Print cmd.Parameters("zap")
Set prm = Nothing
Set cmd = Nothing
Set cnn = Nothing
End Sub