var totalImages = 10; // Total images used

if(document.images){
     mFX = new Array(totalImages);
     for(i = 0; i < mFX.length; i++){
          mFX[i] = new Image();
          }
     mFX[0].src = "/images/butt-home-off.jpg";
     mFX[1].src = "/images/butt-home-on.jpg";
     mFX[2].src = "/images/butt-models-off.jpg";
     mFX[3].src = "/images/butt-models-on.jpg";
     mFX[4].src = "/images/butt-manuals-off.jpg";
     mFX[5].src = "/images/butt-manuals-on.jpg";
     mFX[6].src = "/images/butt-support-off.jpg";
     mFX[7].src = "/images/butt-support-on.jpg";
     mFX[8].src = "/images/butt-contact-off.jpg";
     mFX[9].src = "/images/butt-contact-on.jpg";
     }

function imgFX(img, num){
     if(document.images){
          document.images[img].src = mFX[num].src;
          }
     }