The Apache HTTP Project developers strongly encourage all users to migrate to Apache 2.2, as only limited maintenance is performed for these legacy releases (1.3 and 2.0)
Apache 2.2 offers numerous enhancements, improvements, and performance boosts over the 2.0 codebase. For an overview of new features introduced since 2.0 please see:
http://httpd.apache.org/docs/2.2/new_features_2_2.html
