mono dependencies

[James Green]

Hiya,

I'm trying to install Mono on an up to date Ubuntu system.
Unfortunately, I get the following errors:

jkg at emerald ~ $ sudo apt-get install mono
[...]
The following packages have unmet dependencies:
  mono: Depends: mono-jit (= 0.96-1) but it is not going to be installed or
                 mono-mint (= 0.96-1) but it is not going to be installed
        Depends: mono-utils (= 0.96-1) but it is not going to be installed
        Depends: mono-mcs but it is not installable
        Depends: mono-assemblies-arch but it is not installable
E: Broken packages
jkg at emerald ~ $

Has anyone got any suggestions as to what I can do to work round this,
or are other people having the same problem? For what it's worth, if I
try to install mono-mcs or mono-assemblies-arch directly, apt informs
me they "have no installation candidate".

Thanks,
James.