Update: So many people seem to keep coming to this blog post from Mike Clark's blog that I feel it might make sense to mention that the WeblogPublisher has been incorporated into the CruiseControl distribution already a while ago. In other words, no need to download the stuff from the attached URLs--just use a recent enough version of CruiseControl and you're all set.

Yep. My CruiseControl WeblogPublisher now supports also the LiveJournal API. For now, it only implements clear-text authentication. I'll see if I can squeeze some time for implementing the challenge-based encrypted authentication at some point.

The latest sources and related changes to CruiseControl-2.2 release can be downloaded from the below links:
WeblogPublisher.java
WeblogPublisherTest.java
default-plugins.properties
configxml.html
plugins.html