Column headings do not repeat in SSRS 2008

I've just stumbled upon an odd issue with the Tablix control in SSRS 2008.  I deployed a report on a server a few weeks ago and it is now reporting on enough data to make it span multiple pages.  I wanted the column headings to appear on all pages, not just the first.  However, when I set the RepeatColumnHeaders property on the Tablix to be true, the headings still did not appear on the next page.  After a bit of playing around I enabled Advanced Mode in the Grouping Pane, and had a look at the properties for the top (Static) group in Row Groups.  Under Other, there is a property called RepeatOnNewPage.  Setting this to True made the column headers appear as required.  OK, so that's fine, but I can't help but think that this a a bug in SSRS 2008, and should be fixed by MS.  Looking through the RDL file itself, I can't find anything that would cause the RepeatColumnHeaders property not to behave as expected.

The “Header should remain visible while scrolling” option does not appear to work either; I haven't yet found a workaround for this.