I'm trying to upgrade Evolution from 1.2 to 1.4. As I go through the install process I get the following message:

The installer was unable to resolve dependencies for this install. The following error message may provide information that will allow you to correct the error. Alternatively, you may choose a different product or set of components to install.

Installing libgal2.0-modules-1:1.99.9-0.ximian.6.1[Ximian Evolution]
There are no installable providers of =libgal2.0_5-1:1.99.9-0.ximian.6.1 for libgal2.0-modules-1:1.99.9-0.ximian.6.1[Ximian Evolution]
libgal2.0-modules-1:1.99.9-0.ximian.6.1 is scheduled to be installed, but this is not possible because of dependency problems.
Marking this resolution attempt as invalid.

Any help would be appreciated.