DTS & xp_cmdshell & dtsrun

Hi,

I have two simple DTS packages TestT and TestPkg. I run TestT from TestPck using Execute SQL Task. SQL statement is

EXEC master..xp_cmdshell 'dtsrun /S (local) /E /N TestT'

Problem is, that this task is always completed successfully. Even if TestT fails.
I need to know if TestT fails a do some action (SendEmail). So how can I detect it ? Thanks a lot.