Sql procedure HELP - formal parameter "@psvrno" was not declared

SendNoticeMail : [Microsoft][ODBC SQL Server Driver][SQL Server]The formal parameter "@pSvrNo" was not declared as an OUTPUT parameter, but the actual parameter passed in requested output.(1)

ALTER  PROCEDURE [dbo].[UspMailNoticeSend]
	 @pSender			NVARCHAR(20),
	 @pMailType			TINYINT,
	   @Preceiver			NVARCHAR(20),
	   @ptitle			NVARCHAR(40),
	 @pMain				NVARCHAR(200),
	 @pKeepTerm			TINYINT,
	 @pMoney			BIGINT,
	 @pItemNo			INT,
	 @pItemCnt			INT,
	 @pDur				INT,
	 @pMaxDur			INT,
	 @pIsBind			BIT,
	 @pUnBindCnt		TINYINT,
	   @PenchantStep		TINYINT,
	   @premainMin		INT,
	   @premainBase		INT,
	 @pValidMin			INT = 0,
	 @pSvrNo			SMALLINT = 0,		
	 @pItemSerial		BIGINT			OUTPUT,
	 @pMailNo			INT				OUTPUT, 
	 @pDate				DATETIME		OUTPUT,
	 @pRsMoney			BIGINT			OUTPUT
AS
	SET NOCOUNT ON;
	SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED;
	
	DECLARE   @amailCnt		INT
	DECLARE @aReceiverNo	INT
	DECLARE   @ASEnderMoney	BIGINT
	DECLARE @aEndDate		SMALLDATETIME
	DECLARE @aRead			TINYINT

	SELECT	@pMailNo = 0
		,	@pItemSerial = 0
		,	@pDate = GETDATE()
		,	@pRsMoney = 0
		,   @amailCnt = 0
		,	@aReceiverNo = 0
		,   @ASEnderMoney = 0
		,	@aRead = 0

	
	IF(@pMailType <> 1)
	BEGIN
		RETURN (1);
	END


	IF(@pValidMin > 0)
	BEGIN
		SET @aEndDate = DATEADD("n", @pValidMin, GETDATE())
	END
	ELSE
	BEGIN
		SET @aEndDate = dbo.UfnGetEndDate(GETDATE(), 0)
	END

	SELECT @aReceiverNo = mPcNo FROM dbo.TblPc WHERE mPcNm =   @Preceiver
	IF( @aReceiverNo = 0)
	BEGIN
		RETURN (2);			
	END

	SELECT @pMailNo = ISNULL(MAX(mMailNo), 0) + 1 FROM dbo.TblPcMail WHERE mPcNo = @aReceiverNo
	SELECT   @amailCnt = COUNT(mPcNo) FROM dbo.tblPcMail WHERE mPcNo = @aReceiverNo AND mMailType = @pMailType

	BEGIN TRY
		BEGIN TRAN
			IF( @pItemNo <> 0 )
			BEGIN
				EXEC dbo.UspGetItemSerial @pSvrNo, @pItemSerial OUTPUT; 	
				IF @pItemSerial <= 0  
					BEGIN
						RAISERROR ('Error raised in TRY block.', -- Message text.
									16	, -- Severity.
									2 -- State.  
									);	
					END

				INSERT INTO dbo.TblPcMailItem ( 
						 mRegDate, mSerialNo, mPcNo, mItemNo, mCnt,
						 mDur, mMaxDur, mIsBind, mUnBindCnt, mEnchantStep,
						 mRemainMin, mRemainBase, mEndDate )
				VALUES ( @pDate, @pItemSerial, @aReceiverNo, @pItemNo, @pItemCnt,
						 @pDur, @pMaxDur, @pIsBind, @pUnBindCnt,   @PenchantStep,
						   @premainMin,   @premainBase, @aEndDate)
			END

			IF(   @amailCnt >= 24 )
			BEGIN
				SET @aRead = 2
			END

			INSERT INTO dbo.TblPcMail ( 
					 mRegDate, mPcNo, mMailNo, mMailType, mSender, mTitle, mMain, mMoney, mItemSerial, mRead, mKeepTerm)
			VALUES ( @pDate, @aReceiverNo, @pMailNo, @pMailType, @pSender,   @ptitle, @pMain, @pMoney, @pItemSerial, @aRead, @pKeepTerm)
		
		COMMIT TRAN;
	END TRY
	
	BEGIN CATCH
		ROLLBACK TRAN;
		RETURN (1);
	END CATCH
	
	RETURN (0);

I tryed to execute it via MSSQL seems to run succefully but when server execute it thats the error i got.