[dartho]

What I did was this:

Edit the plugin code and add the following:

$filename = "/path/to/forum/plugin.go";
if (file_exists($filename)) { 


PLUGIN CODE


}

and then create 2 CRON jobs (I did it via cpanel) with the following as the command:
1.

date>/path/to/forum/plugin.go

and scheduled it to run when I wished to enable the plugin

2.

rm /path/to/forum/plugin.go

and scheduled it to run when I want the plugin disabled

You could probably create a php file and use vBulletin's Scheduled Tasks
to do the CRON for you. It ain't pretty, but t works