Display GUI when kill count reaches 5

Ok so I have this kill counter script it works fine and all but the fade part is not working. I got the fade code from the unity wiki site. It compiles and everything but when i test drive it like after I get 5 kills it wont show the warning message on the screen. If i get rid of the if statement if(kills==5) i see the message show up when i start up the game. But I want it to show up after the user kills 5 of the enemies. Again everything compiles with no bugs just that the message does not show up when i kill 5…

var guiSkin :
GUISkin = null;

var kills: int = 0;

var warning : AudioClip;

function OnGUI()
{

    GUI.skin = guiSkin;

    GUI.Label(new Rect(10, 60, 100, 30), "KILLS:");
    GUI.Label(new Rect(110, 60, 150, 30), kills.ToString());
    GUI.skin = null;
}
	
function Start () {
if(kills==5){
guiText.text = "Warning!";

audio.PlayOneShot(warning);

var colors = [Color.red, Color.yellow];
for (i = 0; i < 3; i++) {
    yield Fade.use.Colors(guiText.material, colors, 1.5, false);
}
yield WaitForSeconds(2);
guiText.text=null;
}

}

var kills : int = 1;

function OnDestroy()
{
var tempobj : GameObject = GameObject.FindWithTag("killscore");
var countScript : killcounttest = tempobj.GetComponent(killcounttest);
countScript.kills+=kills;
}

so this is the code thats on my zombie so that everytime it dies it gets added to the killscore gui. It works perfectly fine by i just dont know why if(kills==5) wont work. I mean it compiles just wont print. But if i put it on the function OnGUI it pritns after i get 5 kills just that it wont do the fade effect then.