I'm getting this message in my Drupal installation:
GD Image Filtering Low Quality / Poor Performance
The installed version of PHP GD does not support image filtering(desaturate, blur, negate, etc). It was probably compiled using the official GD libraries from http://www.libgd.org instead of the GD library bundled with PHP. You should recompile PHP --with-gd using the bundled GD library. See http://www.php.net/manual/en/image.setup.php. An implementation of imagefilter in PHP will be used in the interim.
I'm using the default GD library in php on Ubuntu 9.04
What are the exact commands to update this library ?