smb4k depends on net-fs/samba-client which is masked. If you install the non-split samba-packges with client in USE, smb4k can't be installed as it depends on mount-cifs which is blocked by samba. fix:smb4k should also "or"-depend on net-fs/samba[client]
@Samba team: Neither can I find a tracker bug moving the tree back to the monolithic Samba, nor a gentoo-dev thread. A quick grep reveal anything, either. Has this package been overlooked or is it worse?
As far as I can see, this is fixed in smb4k-0.10.5.