I forked the livejournal ruby gem (http://neugierig.org/software/livejournal/ruby/) which seems to be abandoned.
It fixes the well known errors like:
livejournal/entry.rb:174:in `load_prop': unknown prop
which are due to new properties.
It also has some new functionality.
The fork can be found here.
I tried to contact the author, but haven’t heard from him yet.