How to run a DTS as a trusted user in a stored proc

I get an error when i try to run a dts
but when i create a new dts and select the right server and user
everything went well.
Can someone help me?What is the error you receive ?

This is a cut from a microsoft article which may address your problem:
"Also, if the job is owned by a Windows NT domain account and if the package is stored in the SQL Server or SQL Server repository (not as a file), you must start the SQL Server service by using an account from the same domain or an account from a trusted domain. For example, if the SQL Agent job is owned by an account from the USA domain, then the account used to start the SQL Server service must be either from the USA domain or a domain trusted by the USA domain. If the SQL Server is started using a local account, the package fails to run. "

Here is the article:

article (http://support.microsoft.com/default.aspx?scid=KB;en-us;q269074)sql