executing a DTS package from within a stored proc.

How do you execute a DTS package from within a stored proc?create proc newprocedurename as
exec xp_cmdshell "DTSRun /S servername /U username /P password /N packagename"|||True and follow information from books online using DTSRUN utility.|||What if I havent got a username /password assigned to the DB?|||Executewith SA privilege or any other account that has DB access.|||Still no joy...this is what im typing.....

execute xp_cmdshell "DTSRun /S sqlserver /U username /P password /N test_dts1"

sql server is the name of the server, test_dts1 the name of the package.

Anything im doing wrong??