Description:
------------
The order of parameters in a stored procedure must be strictly followed in PDO, otherwise, the parameters will get swapped around in the trace.

Reproduce code:
---------------
CREATE a stored procedure in SQL with two parameters in order:
@param1 nvarchar(100),
@param2 nvarchar(100)

Run a trace in profiler to watch what PDO prepares and executes against the server.

Prepare the EXEC statement but swap the order of the parameters.

If you prepare and execute a query in the form:
$statement = connection->prepare(
  "EXEC dbo.sptest @param2=:param2,@param1=:param1"
);

$statement->execute(array(':param1' => 'test1', ':param2' => 'test2'));

Expected result:
----------------
I would expect that the stored procedure will be prepared by PDO in the form:

declare @p1 int
set @p1=NULL
exec sp_prepare @p1 output,N'@test1 nvarchar(100),@test2 nvarchar(100)',N'EXECUTE runtest @test2 = @test2, @test1 = @test1',1
select @p1

Actual result:
--------------
I would expect that the stored procedure will be prepared by PDO in the form:

declare @p1 int
set @p1=NULL
exec sp_prepare @p1 output,N'@test1 nvarchar(100),@test2 nvarchar(100)',N'EXECUTE runtest @test2 = @test1, @test1 = @test2',1
select @p1