Custom icons don't show

Hello, I see that a few month ago someone had the same issue:topic about the same issue.

The solution there
$content = preg_replace('/http\:\/\/icons\-ak\.wxug\.com\/i\/c\/[a-z]\/(.*?)\.gif/ism', $myIconFolder.'$1'.$myFileType, $content);
doesn’t work for me.

So, today suddenly my custom icons were replaced with default.

I have the filter at the bottom of my functions.php:

add_filter('wp_wunderground_forecast_icon', 'use_custom_wunderground_icons');

function use_custom_wunderground_icons($content=null) { 

    $myIconFolder = 'http://www.example.com/images/myicons';

    $myFileType = '.gif';

    $content = preg_replace('/http\:\/\/icons\-ecast\.wxug\.com\/i\/c\/[a-z]\/(.*?)\.gif/ism', $myIconFolder.'$1'.$myFileType, $content);

    return $content;
}

And today it doesn’t work for some reasen.

Please help.

http://wordpress.org/plugins/wunderground/