I believe you need to install this:
ftp://ftp.andrew.cmu.edu/pub/cyrus-m...-2.1.20.tar.gz
You will have to compile it from source, if you don't want to do that just search for a package for your distro of sasl. I don't know exactly what this is, but my guess would be that it should already be installed, and maybe the installer can't find it.
Try running find / -name libsasl* and see if you come up with anything first.
edit: Oh wait, I didn't realize you were trying to uninstall the program. In that case I'm not too sure. If it were me I'd just ignore it and install from source over top of it. That may not be good advice though so unless you want to risk breaking something I'd not do that lol.
edit2: Rereading your error messages, my best guess here is that the package manager is telling you that you can't uninstall it because it is needed by other programs. See if there's a way to tell the package manager to force the uninstallation. Or maybe those programs/daemons are currently loaded and those libraries are in use, in which case you'll have to stop them all. Maybe try uninstalling it in init 1 or something.
Sorry for all the random guess work, just doing my best to help lol.