// CharacterControllers we touch, disable collision detection.
function OnControllerColliderHit(hit : ControllerColliderHit) {
    hit.controller.detectCollisions = false;
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void OnControllerColliderHit(ControllerColliderHit hit) {
        hit.controller.detectCollisions = false;
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def OnControllerColliderHit(hit as ControllerColliderHit):
        hit.controller.detectCollisions = false