Ärger mit auth DIGEST in apache nach update auf ubuntu Feisty Fawn (7.04)?

Folgenden Fehler hat apache ausgespuckt:

Invalid command ‚AuthDigestFile‘, perhaps misspelled or defined by a module not included in the server configuration

En. abstract: This article describes, what to do, when you get this error abow. The problem is, that youre configuration of apache are not compatible to the new version of apache (2.2). I will tell you, how to solve this problem using italic letters for english version.