Dynamically Changing Configuration File Path

Before I launch into a long description of the issue, I was wondering whether its possible to dynamically amend the file path held in a configuration string? (I'm looking at the Package Configurations Organizer)

Basically recreating the /CONF switch in the dtexec utility

So a parent package could somehow tell a child package to pull its configuration from a selection of different xml config files at run time... I couldn't see a variable in the child package to set from the former

My only idea at the moment is to replace the Execute Package Task with an Execute Process Task, and directly invoke the child using dtexec & an expression to dynamically set the /CONF switch..

thanks

James