Flash CS3: Debugging getting line numbers.

It's helpful in debugging code to get the line number and the name of the file. This is easy if your using the MXML compiler, via the -verbose-stacktraces and -debug but what about using Flash CS3?  At least on my system by default null errors during runtime look like:

Error #1069: Property null not found on ...your class and there is no default value

at com.yourclass.::MyClass$someFunction()

Which isn't particularly easy to trouble shoot. But if you go File>Publish Settings and checkmark Permit Debugging you can get the far more useful, where 138 is the line number

at com.yourclass::MyClass$someFunction()[C:\\com\yourclass\MyClass.as:138]