if(document.all) {
 //IE	  
 function popup (page) {
  window.open(page,'','width=600,height=395,scrollbars,top=150,left=200');
  }
 }

else if(document.layers) {
 //NN4
 function popup (page) {
  window.open(page,'','width=600,height=395,scrollbars,top=200,left=280');
  }
 }
    
else if(document.getelementbyid) {
 //NN6
 function popup (page) {
  window.open(page,'','width=600,height=395,scrollbars,top=200,left=280');
  }
 }
					
else {
 //ALL
 function popup (page) {
  window.open(page,'','width=600,height=395,scrollbars,top=200,left=280');
  }
 }