The most common method used to execute DTS packages from within T-SQL scripts
or stored procedures, is via xp_cmdshell and dtsrun.
Whilst this works, and is very simple the implement, it lacks flexibility.
The SQL Server 2000 version of dtsrun allows you to pass
GlobalVariables on the command line, which improves it's appeal,
but the security restrictions on xp_cmdshell can still limit it's appeal.