Are any poclbm processes actually running and staying idle or are they simply not starting in the first place?
I must apologize for my lack of Linux skills, I have no idea how to monitor running processes under Linux and therefore no idea how to check if they start at all.
In Ubuntu you would select from the drop down menus at the top: System -> Administration -> System Monitor
Processes shows running tasks,
Resources shows (among other things) network utilization.
Why don't you try running poclbm on its own and see if it runs OK. This way you eliminate one variable (CP). Be sure to pass it the correct parameters.