Using Access 97 I was able to get around the problem by creating an Excel sheet with the text (in my case field headers) in a vertical position. In my Access report I went to "Insert, Object, Microsoft Excel Worksheet" and placed the vertical text in the report. At this point it's pretty much a graphic but you can edit the original by double clicking on your newly placed object. You'll likely need to re-align your fields to the graphic.
Good luck.