function setcurrent(linkid) {
var classname1 = 'current';
var classname2 = 'lnk';
var obj=document.getElementById("mainmenu").getElementsByTagName("a");
   for(i=0; i <obj.length;i++) 
   { 
      if(i == linkid) 
      { 
         obj[i].className = classname1; 
      } 
      else 
      { 
         obj[i].className = classname2; 
      } 
   } 
}
function showblock(blockId){

 var divid="content_block";
 //setcurrent(blockId-1);
 for (var i=1;i<=4;i++){
	 if (i == blockId) {
	  document.getElementById(divid+i).style.display="block";
	 }
	 else
	 {
		 document.getElementById(divid+i).style.display="none"
	 }
 }


}