function chk_login(login, realm) {
    if (login.match("^[A-Za-z0-9_]+$").length > 0) {
        $.get("./include/ajax_functions.php", {func: 'chk_login', login: login, realm: realm }, function(data){
            if( data.length > 0 )
            {
                var new_left = $("#auth_login").offset().left - 255;
                $("#auth_info_block").stop(true);
                $("#auth_info_block").offset({left:new_left});
                $("#auth_info_block").css("opacity", "0");
                $("#auth_info_text").html(data);
                $("#auth_info_block").animate({opacity: "1", left: "+=200"}, 1000).delay(3000).animate({opacity: "0", left: "+=200"}, 1000);
            }
        })
    } else if (login.match("[^A-Za-z0-9_]").length) {
            var new_left = $("#auth_login").offset().left - 255;
            $("#auth_info_block").stop(true);
            $("#auth_info_block").offset({left:new_left});
            $("#auth_info_block").css("opacity", "0");
            $("#auth_info_text").html("opacity");
            $("#auth_info_block").animate({opacity: "1", left: "+=200"}, 1000).delay(3000).animate({opacity: "0", left: "+=200"}, 1000);
    }
    
};