Portals Initial Sort causes child records to disappear

If i set an initial sort order for a portal some of the child records do not appear in the portal while other records appear twice. Clicking on a column header to re-sort solves the problem.
If there is no ‘initial sort’ definied everything works fine.
Please confirm.

Servoy 2.2final
MacOS X 10.4/Win 2000
Java 1.4.2