Can't sudo apt-get install ´insert program´

[Balthazard]

Like the title states. I cant use Sudo apt-get install.
every time I try to install something I get the following error.

you probably want to use sudo apt-get -f install.

And

These packages do not have a sufficient requirement.
kmenc15: Requirment: kdelibs4 (>= 4:3.3.2-3) But is not installable
Requirment: libqt3c102-mt (>= 3:3.3.3) But is not installable

I have try'ed the sudo apt-get -f install but it didn't do the job.
Hope someone knows how to solve this.

Ps.:I am running Kubuntu 7.04.

[Proto]

Hmm... a problem of conflicting dependencies... you probably tried to install those before from deb packages from the debian repository but those cause conflicts themselves and they decided that they didn't want to work after all. If that's not the case, can you do a apt-get dist-upgrade?

[Balthazard]

Yup I did install some stuff from the repositry but I dont think thats the problem.

I try'ed sudo apt-get update and this is what I get.:

W: GPG error: Repository for Ubuntu feisty Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY BC40ED2499419355

and sudo apt-get upgrade gives me the same error as stated in the first post.

[Proto]

Could you state the whole error log that it gives you in both cases? Anyway, you might want to post this in the ubuntuforum in the meanwhile, since this seems to be a more or less common problem they might have a handy answer