Stevan, most likely the calendar problems you experienced came from insufficient support for time zone information in one of the involved components. As mentioned in the article, this is not a problem of SyncML itself but of the data format used for exchanging calendar events. Support for time zones is improving, but much more slowly that I had hoped. Synthesis added support for it in their 3.x engine; not sure about eGroupware.
Many of the traditional SyncML clients only supported UTC or local time. Neither one nor the other are sufficient when dealing with recurring events in many different time zones - in other words, a multi-national enterprise scenario.