HELP:sorting list of outline numbers

[Felix Collins]

Hi All,
does anyone know any cleaver tricks to sort a list of outline numbers.

An outline number is a number of the form...    1.2.3

they should be sorted in the following way...

1
1.1
1.2
1.12

python's alpha sort (by design) sorts them...

1
1.1
1.12
1.2

That's no good for me.
I'm planning on splitting the strings into multiple lists of ints and 
doing numerical sorts.

Thanks for any clever ideas that might make it easier.

Felix