GUI.DrawTexture gives error

I am trying to draw a texture to the screen using code, but keep getting the error below. Please help me.

Assets/01SkugPezz/WeaponSelection.js(20,16): BCE0023: No appropriate version of ‘UnityEngine.GUI.DrawTexture’ for the argument list ‘(UnityEngine.Rect, UnityEngine.GUITexture)’ was found.

var fireButton :GUITexture;
function OnGUI() 
{
   if(!fireButton)
   { 
      Debug.LogError("Assign a Texture in the inspector.");
      return;
   }
 GUI.DrawTexture( new Rect(0, 50, 50,50), fireButton);

 }

The second parameter to this function should actually be a Texture2D (ie, a standard Unity texture asset). A GUITexture is a component that can be added to an object to make it display a texture on the GUI automatically without a DrawTexture call.