Hi,
it's like in the topic: I can't mount multisession CD burned with K3B. There's no problem with CDs burned in one session.
Every multisession CD seems to be OK, since I can mount it using "mount". But after inserting such CD Device Manager plasmoid nor Dolphin show nothing. Only K3B shows CD's label but also wont install it.

This appears to be a lacking of predicates, used by Solid to show the list of actions.

Which version of KDE SC do you use?
If you use KDE SC 4.3, please report a bug at bugs.kde.org, aganist Solid in KDELibs.

Otherwise, please update to 4.3, and re-test.

I'm using KDE 4.3.3 and Fedora 12. It's the newest version available in repos.
I've reported a bug 218469.