Perfect Server Ubuntu 11.04 Build Essential

[lobius]

I am stuck on step 18, Install Jailkit.

I double checked my sources.list. Matches the earlier step. Nothing wrong there.

The error message follows:

apt-get install build-essential
Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 build-essential : Depends: g++ (>= 4:4.4.3) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Is there another repository where I can get build essential?

I'd skip it but the tutorial indicates there would be problems later on if I did.