Completing arguments containing the colon character

[Gabor Maghera <gmaghera@xxxxxxxxx>]

We use a naming standard for Perforce specs of the form
"<username>::<arbitrary>".  Zsh autocompletion cannot process these entries,
due to the colon character being used as a list separator by its mechanism
(as I understand).

Is there a way to make it work?  I've been perusing the man page for
zcompsys, as well as the _perforce completion module, but I'm not sure it's
possible.

Here is an example of what the erroneous completions look like:
% p4 client -o p4droid<tab><tab>
p4droid                                          --
:PerforceTriggers:2009/12/29 root /opt/local/perforce/trigger_scripts
'Created by p4droid. '
p4droid                                          -- :triggers:2009/12/18
root /Workspace/trigger_test 'Created by gabor.maghera. '

The full entry names are p4droid::PerforceTriggers and p4doird::triggers.

Thanks in advance,
Gabor