when I try to install evolution-webcal apt tries to remove evolution, evolution-exchange, evolution-plugins, and gnome-desktop-environment. This cannot be good. Does anyone else have this problem, and is there a solution?

I use debian lenny and my updates are all up to date. That means that evolution-common is at 2.10.3-1 and evolution-data-server is at 1.12.2-1. The version of evolution-webcal that I want is 2.12.0-1... Any help would be appreciated. TIA.

That sounds to me as though the Gnome updates are in-between states, with evolution-webcal ahead of the rest of evolution. The problem is that this can start a chain reaction: the update of one thing causes the (suggested) removal of evolution. But evolution is a requirement (a dependency) of the gnome-desktop-environment meta-package, so then gnome-desktop-environment is marked for removal. There are a couple of solutions, but maybe the easiest is to just not do the update. Try again in a few days and see what it looks like then. Often the other packages will catch up quickly and then you can go ahead.

A longer term solution is to remove the gnome-desktop-environment meta-monster using apt-get and then use aptitude to mark everything else as good to stay. (That way, you won't get "suggestions" to use auto-remove to remove all the Gnome packages that you still want.) This solution used to work, but given all the changes in apt-get itself, I'm not sure if it would anymore. Anyhow, this solution looks like this: I just checked it on my system (with gnome-core - I don't have gnome-desktop-environment), and it still seems to work. Still, it's more involved, and maybe you like the meta-package.