I found out how to get the effect I wanted both in NetSurf and in Firefox by avoiding the "height" attribute. I put everything inside a containing box and for the left- and right-hand columns set the attributes "top" and "bottom" to 0. Then their heights get sucked to that of the middle column.
-- Gavin Wraith (ga...@wra1th.plus.com) Home page: http://www.wra1th.plus.com/