Syncing multiple calendards between Zarafa (or any other groupware) and Android over ActiveSync is not possible due to limitation in Android. However, Zarafa can export calendars via CalDav, and there is an Android apps which adds CalDav calendars to the native calendar system.
ActiveSync is the Microsoft way of syncing data, and is well established in the business ecosystems and thus also in groupware sync solutions like z-push. However, sharing multiple calendars via ActiveSync is not possible with Android without any special hacks. Additionally, ActiveSync is patented and copyrighted and as as result for each device which is able to sync via ActiveSync a fee is payed to Microsoft.
As a result, the sync between multiple calendars in Zarafa and Android does work now flawlessly. An additional bonus is that you are free to choose the colors of the calendars, in contrast to the ActiveSync implementation where you are stuck with a random color. ? 2b1af7f3a8