Start debug on a running job

How can I start a debug session for a job that is already running on the 
server? This can be useful when a job has run into an error. On the 
iSeries itself, I would use a STRSRVJOB (Start Service Job), and then use 
STRDBG (Start Debug). What is the equivalent in WDSCi?

I have tried the configuration My iSeries Job in the Debug dialog window. 
In that window, I have entered the job information of the job I want to 
debug. Now, when I click on the button Debug, a window is displayed with 
the text 'Press OK and invoke your iSeries application to continue'. The 
problem is that the application is already running. How do I connect to or 
'tap into' that running job?

Ewout