_git Completion and custom commands

[Conrad Irwin <conrad.irwin@xxxxxxxxx>]

Hi Zsh,

I finally got round to trying out zsh today, and wow is it cool — I
don't believe I've been stuck on bash for all this time :).

The one issue I've found is that the _git completion function (as of
4.3.10 shipped with Debian testing) does not include custom commands
(though it does include aliases).

(For those of you unfamiliar with git, any executable in your path
with a name like git-* can be called as git * with no hyphen)

My question is then: how would I add my custom commands' names to the
list already completed by _git (without completely overriding or
modifying the system-wide configuration)?

Thanks for your time,

Conrad