Center column fixed height with scrollbar

Hello,

I am working on a page where I would like the center column to have a fixed height displaying blog posts that the reader can simply scroll down through to read. I have found a couple of posts here, but there was no outcome to the problem posted.

I tried modifying the css (through the theme options) to include max-height, but this had no effect.

Any help would be much appreciated!

Thanks!

grabutty