If you're using a package, uninstall it.
Then use the binary install from the Calibre site.
LINK Let it install to the default directory (opt). You may need to re-point it to your library. You may, or may not, lose your preferences this one time (depending on the uninstall effects.) Not too difficult to fix.
It works perfectly fine on my 10.04 lappy. When Calibre is updated, just do the binary install again, you won't lose preferences or any other configuration. Never had an issue in the last year with doing this.