function swapClass(){
 var i,x,tB,j=0,tA=new Array(),arg=swapClass.arguments;
 if(document.getElementsByTagName){for(i=4;i<arg.length;i++){tB=document.getElementsByTagName(arg[i]);
  for(x=0;x<tB.length;x++){tA[j]=tB[x];j++;}}for(i=0;i<tA.length;i++){
  if(tA[i].className){if(tA[i].id==arg[1]){if(arg[0]==1){
  tA[i].className=(tA[i].className==arg[3])?arg[2]:arg[3];}else{tA[i].className=arg[2];}
  }else if(arg[0]==1 && arg[1]=='none'){if(tA[i].className==arg[2] || tA[i].className==arg[3]){
  tA[i].className=(tA[i].className==arg[3])?arg[2]:arg[3];}
  }else if(tA[i].className==arg[2]){tA[i].className=arg[3];}}}}
}