var iPath = "imgs/";
var iExt = "gif";
var suffix = new Array("1","0");

function preLoad() {
  if (document.images) {
	var argLen = arguments.length;
	for(var i = 0; i < argLen; i++) {
	  var arg = arguments[i];
	  var sufLen = suffix.length;
	  for(j = 0; j < sufLen; j++) {
		var suf = suffix[j]
		self[arg + "_" + suf] = new Image();
		self[arg + "_" + suf].src = iPath + arg + "_" + suf + "." + iExt;
	  }
	}
  }
}

function rollOver(iName, iState, iNum) {
	if (!iNum) { iNum = ""; }
	if (document.images && self[iName + "_" + iState]) {
		document.images[iName+iNum].src = self[iName + "_" + iState].src;
	}
}