Today, I have published another article on fundamental of RAISERROR in SQL Server 2005. Its all about internal of RAISERROR, how to use it, sp_addmessage, use them inside TRY-CATCH etc. If you really interesed, Here is my complete article
A Closer Look Inside RAISERROR – SQLServer 2005
Abhijit's Blog 
Thank you good Article.
I ‘ve a question.
we can do this in Sqlserver2000 ?
BEGIN TRY
DECLARE @Intval int;
SET @Intval = 1/0; — Devide by Zero Error
END TRY
BEGIN CATCH
RAISERROR (50009, 11, 1); — 50009 is our pre-defined error that are stroed using sp_addmessage
END CATCH;
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