Looking at Language.php, it is clear that we now have 16 + 2 = 18 namespaces.
Yet in DefaultSettings.php, you do not initialise all the elements in the
$wgNamespacesWithSubpages = array( -1 => 0, 0 => 0, 1 => 1,
2 => 1, 3 => 1, 4 => 0, 5 => 1, 6 => 0, 7 => 1, 8 => 0, 9 => 1, 10 => 0, 11 => 1);
which is only the first 12 namespaces plus Special.
As a good programming practise, it would be appropriate to initialise ALL values in this array to
something meaningful. Currently namespaces -2 (Media), and 12-15 (Help, Help_Talk, Category and
Category_Talk) do not get a specifically assigned entry in the array.
The next statement in DefaultSettings.php relating to $wgNamespacesToBeSearchedDefault has a
I think this stems from the growth of MediaWiki from 12 to 16 namespaces (plus the two negative-
numbered special spaces).
And while the comment above these two statements says
See Language.php for a list of namespaces.
It would also make some sense to provide a pointer to a list of the namespace NUMBERS, which is,
after all, what the arrays are initialised using (rather than namespace NAMES). These definitions
are laid out in module Defines.php
OS: Windows 2000