an action/radio option only available in a trigger?

[gothicv]

I couldn't find the answer to this in the searh thing, so I figured id ask here. I would like to have a radio option available only in a specific area - for my soldiers to call for backup when they reach the end zone.

[deaddog]

You could try a repeating trigger.

type:anybody preset
condition: player in thislist

on activation:
  actionid=vehicle player addaction [whatever]

on-deactivation:
   player removeaction actionid