A small problem with the new inet and cidr types

It seems that we have a small problem with the operators and functions
in the inet and cidr types.  If the value in a field is null then the
backend crashes when you try to apply one of the operators or functions
on it.  I have a small patch ready to fix the functions but I'm not
sure what the behaviour should be for the operators.  For the functions
I return an empty string if the argument is null except for masklen()
which returns 0.  Should masklen return 32?

At Marc's request I am holding my patch until 6.4 is frozen.

-- 
D'Arcy J.M. Cain <darcy@{druid|vex}.net>   |  Democracy is three wolves
http://www.druid.net/darcy/                |  and a sheep voting on
+1 416 424 2871     (DoD#0082)    (eNTP)   |  what's for dinner.