function MouseOver_LeftNav(BttnName) {
    Img = document.images['BttnMark'+BttnName];
    Img.src = '/images/sq_on1.gif';

    Img = document.images['BttnRightMark'+BttnName];
    Img.src = '/images/triangle.gif';
}
function MouseOver_LeftNavSub(BttnName) {
    Img = document.images['BttnSubMark'+BttnName];
    Img.src = '/images/sq_on_sub.gif';

    Img = document.images['BttnRightSubMark'+BttnName];
    Img.src = '/images/triangle.gif';
}
function MouseOut_LeftNav(BttnName) {
    Img = document.images['BttnMark'+BttnName];
    Img.src = '/images/sq_off.gif';

    Img = document.images['BttnRightMark'+BttnName];
    Img.src = '/images/noimage.gif';
}
function MouseOut_LeftNavSub(BttnName) {
    Img = document.images['BttnSubMark'+BttnName];
    Img.src = '/images/sq_off_sub.gif';

    Img = document.images['BttnRightSubMark'+BttnName];
    Img.src = '/images/noimage.gif';
}

var SubscrEMailFirstClick=true;
function ValidEMail(EMail){
  if ((EMail.value.search('@') > -1)&&(EMail.value.search('.') > -1)) return true;
  alert('Пожалуйста проверьте и исправьте введенный E-Mail адрес.');
  EMail.focus();
  return false;
}
function SubscrEMailClicked(EMail){
  if (SubscrEMailFirstClick) EMail.value='';
  SubscrEMailFirstClick=false;
}