I'd suggest user the user list and access levels instead of a text file.
User list might contain:
CanUse:*!*@111.111.111.111
CanUse:*!*@222.222.222.222
Etc.
Then your on TEXT would be:
on CanUse:TEXT:*:#: { }
You can, of course use some name other than "CanUse" or just use a number instead of a name for the level.