Dead lock issue

Hi,
I am running Store Procedure in sql server 2005 but sometimes i see deadlock error.
Could you please advice me what could be the problem and where i need to identifiy?
I am doing insert/update inside the procedure.
This is written by third party.

Please see the Store Procedure
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE procedure [dbo].[TrkOrd]
(
@CallType INT = 1
,@App VARCHAR(50)
,@OrdNum INT = 0
,@OrdDt DATETIME = NULL
,@OrigReq XML = ''
,@OrdReq XML = ''
,@Response XML = ''
,@SubmitFlag BIT = 0
,@Exceptions VARCHAR(MAX) = ''
)
AS
BEGIN
---BEGIN TRAN T1
DECLARE @Ver AS SMALLINT
IF @CallType = 1
BEGIN
SELECT TOP 1 @Ver = ISNULL(Ver,0) + 1 FROM OrdProcStatus
WHERE App = @App AND OrdNum = @OrdNum
ORDER BY Ver DESC
IF @Ver is NULL
Set @Ver = 0
Insert INTO OrdProcStatus(App,OrdNum,OrdDt,OrigReqMsg,Ver)
VALUES(@App,@OrdNum,@OrdDt,@OrigReq,@Ver)
--IF @@ERROR <> 0 GOTO X
END
ELSE IF @CallType = 2
BEGIN
SELECT TOP 1 @Ver = Ver FROM OrdProcStatus
WHERE App = @App AND OrdNum = @OrdNum
ORDER BY Ver DESC

UPDATE OrdProcStatus
SET
OrdReqMessage = @OrdReq

WHERE App = @App AND OrdNum = @OrdNum AND Ver = @Ver
--IF @@ERROR <> 0 GOTO X
END
ELSE IF @CallType = 3
BEGIN
SELECT TOP 1 @Ver = Ver FROM OrdProcStatus
WHERE App = @App AND OrdNum = @OrdNum
ORDER BY Ver DESC

UPDATE OrdProcStatus
SET
ResponseMessage = @Response
,SubmitFlag = @SubmitFlag
WHERE App = @App AND OrdNum = @OrdNum AND Ver = @Ver
--IF @@ERROR <> 0 GOTO X
END
ELSE IF @CallType = 4
BEGIN
SELECT TOP 1 @Ver = Ver FROM OrdProcStatus
WHERE App = @App AND OrdNum = @OrdNum
ORDER BY Ver DESC

UPDATE OrdProcStatus
SET Exceptions = @Exceptions
WHERE App = @App AND OrdNum = @OrdNum AND Ver = @Ver
--IF @@ERROR <> 0 GOTO X
END
--COMMIT TRAN T1
SELECT 1 AS Success FOR XML RAW--, XMLDATA
--RETURN
--X:
--ROLLBACK TRAN T1
--SELECT 0 AS Success FOR XML RAW--, XMLDATA

END

Appreciate your kind help!
thanks

How are you sure this proc is the cause of the issue? Are you running any trace flags? also , is this deadlocking against another SPID running this same code? Please more information. Thanks!

Michael,
Thanks for your response.
we are running same stored proc in another few application which has same set of tables but its never having locking issue, only particular one applicaiton having dead lock issue.
Thanks,

Trace it using profiler.
In profiler select the deadlock and deadlock graph within lock columns.
Run your profiler for specific database and then run your query on another window.
Stop the trace and you will see the deadlock victim in deadlock graph.

Thanks Ashish.
If i turn Profiler ON then it won't put much overhead on DB?

The code looks OK. I would check if indexes are not being used (table scans) by examining the estimated query plan. Most deaqdlocks can be solved by proper indexing and speed. I am guessing that the query is slow or fired very often. If is slow, speed it up.. If it is fired often, then make it fast[]

Thanks Michael.
If code is ok then what causes to dead lock?
Otherthing, its not dead locking in other application but only one application.

Hi,
I'll suggest you to go back and check the indexes of the table schema... I found a very interesting article on deadlocking issues.
http://consultingblogs.emc.com/jame...ous-deadlock-and-the-not-so-logical-lock.aspx
and its worth reading.
tell me if this helps.
Rohit