function swap()
	{var i,x,tB,j=0,tA=new Array(),arg=swap.arguments;    //define variables
	if(document.getElementsByTagName)
		{for(i=4;i<arg.length;i++)                          //read function arguments
			{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];}
				}
			}
		}
	}