apt-get logic?

[Svante Signell]

During a recent update with apt-get my installed
wmaker-[plain,kde,gnome]_0.6.1.1-1 was REMOVED since in
wmaker_0.61.1-4 all these packages were merged into one bigger
package. What is the loqic behind removing my wmaker installation
instead of proposing the new package?
I had to 'apt-get install wmaker' to get wmaker back!