var ie    = (document.all) ? true : false;
var ns6   = (document.getElementById && !ie) ? true : false;
var ns    = (document.layers) ? true : false;

var doc_start = (ie) ? "document.all[" : (ns6) ? "document.getElementById(" : "document[";
var doc_end   = (ns6) ? ")" : "]";
var style     = (ie || ns6) ? ".style." : ".";

function show_shutter_content( tab, maxtab )
{
for ( i=0; i<maxtab; i++ ) 
  {
  if ( i == tab )
    {
      eval(doc_start + "'shutter_content" + i + "'" + doc_end + style + "display = ''"); 
    }
  else
    {
      eval(doc_start + "'shutter_content" + i + "'" + doc_end + style + "display = 'none'"); 
    }
  }
}