var aryImages = new Array(2);
  var iNavCnt_R = 9;
  var iNavCnt_T = 7;
  var iNavCnt_L = 10;
  var iCnt = 0;
  
  for (var j=0;j<iNavCnt_R;j++)
  	aryImages[iCnt++] = new Array("/images/nav_right_swap_blk_" + (j+1) + ".gif","/images/nav_right_swap_" + (j+1) + ".gif");
  for (var k=0;k<iNavCnt_T;k++)
  	aryImages[iCnt++] = new Array("/images/nav_top_" + (k+1) + ".gif","/images/nav_top_swap_" + (k+1) + ".gif");
  for (var m=0;m<iNavCnt_L;m++)
  	aryImages[iCnt++] = new Array("/images/nav_left_swap_blk_" + (m+1) + ".gif","/images/nav_left_swap_" + (m+1) + ".gif");

  for (i=0;i<aryImages.length;i++) 
  {
    var preload = new Image();
	for (var j=0;j<2;j++)
    	preload.src = aryImages[i][j];
  }
  function swap(navIndex,imgIndex) 
  {
     document['imgNavSwap' + navIndex].src = aryImages[navIndex][imgIndex];
  }