busybox

This sed patch can only be described as "duh".  Stat the source file, chmod
the _destination_ file.  (Ah hah!  That works _much_ better...)  I
implemented the behavior, I just forgot to test this corner of it.  My fault,
sorry...

No, gnu sed -i doesn't preverve ownership information.  I checked.
Permissions, yes, ownership info, no.

Rob