// ROLLOVER

if (document.images) { 
  img1on = new Image();
  img1on.src =  '/images/nav_contact_on.gif';    
  img2on = new Image();
  img2on.src =  '/images/nav_home_on.gif'; 
  img3on = new Image();
  img3on.src =  '/images/nav_overview_on.gif';
  img4on = new Image();
  img4on.src =  '/images/nav_practice_on.gif';
  img5on = new Image();
  img5on.src =  '/images/nav_profile_on.gif';
  img6on = new Image();
  img6on.src =  '/images/nav_articles_on.gif';
  img7on = new Image();
  img7on.src =  '/images/nav_events_on.gif';
  img8on = new Image();
  img8on.src =  '/images/nav_links_on.gif';    
  
  img1off = new Image();
  img1off.src = '/images/nav_contact_off.gif';
  img2off = new Image();
  img2off.src = '/images/nav_home_off.gif';
  img3off = new Image();
  img3off.src = '/images/nav_overview_off.gif';
  img4off = new Image();
  img4off.src = '/images/nav_practice_off.gif';
  img5off = new Image();
  img5off.src = '/images/nav_profile_off.gif';
  img6off = new Image();
  img6off.src = '/images/nav_articles_off.gif';
  img7off = new Image();
  img7off.src = '/images/nav_events_off.gif';
  img8off = new Image();
  img8off.src = '/images/nav_links_off.gif';
}

function imgOn(imgName) {
  if (document.images) {
    document[imgName].src = eval(imgName + "on.src");
  } 
}

function imgOff(imgName) {
  if (document.images) {
    document[imgName].src = eval(imgName + "off.src");
  }
}