function isEmailAddr(email) {
    if (email.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
        return true;
    else
        return false;
}

// Old version of the check
function isMultiEmailAddr2(email) {
    if (email.search(/^( *,* *\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+)+$/) != -1)
        return true;
    else
        return false;
}

function isMultiEmailAddr(email) {
    if (email.search(/^ *,* *\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+( *,+ *\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+)*$/) != -1)
        return true;
    else
        return false;
}