Problem with controller and points

Hey there i have a big problem wich i just cant solve :S i have a controller and some rings i fly through and then it adds points to a GUI text

here is the controller script

Code (csharp):

1. #pragma strict
2.  
3. var rotation = 85;
4. var bankRotation = 15;
5. var currSpeed = 15.0;
6. var startSpeed = 15.0;
7. var stop = 15.0;
8. var notBegun = 0.0;
9.  
10. var delayTime = 0.5;
11. var acutTime = 0.0;
12. var currTime = 0.0;
13.  
14. var pointField : GUIText;
15. var timerField : GUIText;
16. var restartField : GameObject;
17. var submitField : GameObject;
18. var highscoreField : GameObject;
19. var backToMenu : GameObject;
20. var add1Points = 1;
21. var add5Points = 5;
22. var add10Points = 10;
23. var addTime01 = 3;
24. var addTime02 = 5;
25.  
26. var score : float;
27. var timer : int;
28.  
29. var isDone = false;
30. var timerBool = false;
31. var isUsingMouse = false;
32. var begun = false;
33. var checkIfBegun = true;
34.  
35. var explosionPrefab : Transform;
36.  
37. function Awake () {
38. pointField = GameObject.Find("GUI/txt_Points").GetComponent(GUIText);
39. timerField = GameObject.Find("GUI/txt_Timer").GetComponent(GUIText);
40. restartField = GameObject.Find("GUI/Texture_Restart");
41. submitField = GameObject.Find("GUI/Texture_Submit");
42. highscoreField = GameObject.Find("GUI/Texture_HighScore");
43. backToMenu = GameObject.Find("GUI/Texture_BackToMenu");
44. restartField.transform.position = Vector3(0,45,0);
45. submitField.transform.position = Vector3(0,45,0);
46. highscoreField.transform.position = Vector3(0,45,0);
47. score = 0;
48. timer = 20;
49. UpdateText();
50. }
51.  
52. function OnTriggerEnter(collider : Collider) {
53.     if(collider.gameObject.tag == "Ring1") {
54.         score += add1Points;
55.         timer += addTime01;
56.     }
57.     if(collider.gameObject.tag == "Ring5") {
58.         score += add5Points;
59.         timer += addTime02;
60.     }
61.     if(collider.gameObject.tag == "Square") {
62.         score += add10Points;
63.         timer += addTime02;
64.     }
65.     if(collider.gameObject.tag == "Ground") {
66.         Instantiate(explosionPrefab, transform.position, transform.rotation);
67.         restartField.transform.position = Vector3(0,0,0);
68.         submitField.transform.position = Vector3(0,0,0);
69.         highscoreField.transform.position = Vector3(0,0,0);
70.         backToMenu.transform.position = Vector3(0,0,0);
71.         isDone = true;
72.         Destroy (gameObject);
73.     }
74. }
75.  
76. function Update () {
77.     if(checkIfBegun == true) {
78.         Begun();
79.     }
80.  
81.     if(isUsingMouse == false) {
82.     var pitch = Input.GetAxis("Vertical") * rotation;
83.     var roll = Input.GetAxis("Horizontal") * rotation;
84.     var bank = Input.GetAxis("Bank") * bankRotation;
85.    
86.     pitch *= Time.deltaTime;
87.     roll *= Time.deltaTime;
88.     bank *= Time.deltaTime;
89.    
90.     transform.Rotate(pitch,0,-roll);
91.     transform.Rotate(0,roll / 5,0,Space.Self);
92.     transform.Rotate(0,bank,0,Space.Self);
93.     }
94.     else {
95.     var pitchM = Input.GetAxis("Mouse Y") * rotation;
96.     var rollM = Input.GetAxis("Mouse X") * rotation;
97.     var bankM = Input.GetAxis("Bank") * bankRotation;
98.    
99.     pitchM *= Time.deltaTime;
100.     rollM *= Time.deltaTime;
101.     bankM *= Time.deltaTime;
102.    
103.     transform.Rotate(pitchM,0,-rollM);
104.     transform.Rotate(0,rollM / 5,0,Space.Self);
105.     transform.Rotate(0,bankM,0,Space.Self);
106.     }
107.    
108.     CheckTimer();
109.     UpdateText();
110.     CheckScore();
111.    
112.     transform.Translate(0,0,currSpeed * Time.deltaTime);
113. }
114.  
115. function Begun () {
116.     if(begun == false) {
117.     rotation = notBegun;
118.     bankRotation = notBegun;
119.     currSpeed = notBegun;
120.     stop = notBegun;
121.     }
122.     else {
123.     rotation = 85;
124.     bankRotation = 15;
125.     currSpeed = 15.0;
126.     stop = 15.0;
127.     checkIfBegun = false;
128.     }
129. }
130.  
131. function UpdateText() {
132.     pointField.text = score.ToString();
133.     timerField.text = timer.ToString();
134. }
135.  
136. function CheckTimer () {
137.     if(timer == 0) {
138.         bankRotation = 0;
139.         rotation = 0;
140.         stop = 0;
141.         currSpeed = 0;
142.         restartField.transform.position = Vector3(0,0,0);
143.         submitField.transform.position = Vector3(0,0,0);
144.         highscoreField.transform.position = Vector3(0,0,0);
145.         backToMenu.transform.position = Vector3(0,0,0);
146.         isDone = true;
147.         Destroy (gameObject);
148.     }
149.     if(timerBool == true  timer > 0) {
150.         timer -= 1;
151.         timerBool = false;
152.         yield WaitForSeconds (1);
153.         timerBool = true;
154.     }
155. }
156. function CheckScore () {
157.     if(begun == true  isDone == false) {
158.     currSpeed = startSpeed + score / 4;
159.     }
160. }

i have a collider set to is trigger and witht the tag Ring1 on it

the problem is that it adds 2 points each time i fly through instead of 1
how can i solve this problem

Best Regards

Pierre skinnerup