AFAIK it has been a long-standing "bug" ("upstream") that pulseaudio included the esound compatibility as a dependency. Maybe 10 years ago it made sense. I spotted this package yesterday in my Ubuntu 12.04 and purged it with no adverse effects.

I have just done that on my N900. Seems OK. I don't want to start a discussion on what CSSU should do and what it should not do, but I personally think that it's about time to stop caring about one-to-one compatibility with Nokia PR/SSU, so CSSU-team could test/check if this dependency is actually needed, and if not, remove it.