I've just released new version of fzTagPlugin, which introduces Spanish translation files created by Alex Otero.
fizyk: Spanish translation (Alex Otero)
fizyk: ability to create multiple instances of different tag clouds
fizyk: ability to create tag cloud out of custom tag collection
fizyk: updated TagCanvas to 1.6.1
Additional plugin's resources:
On a side note, I'm slowly working on a private message system for sfDoctrineGuard powered symfony websites. Current code can be found here. It won't be anything fancy, and would rather need some customizations. At least in first few versions.