Cross posting to front and to og causes content to drop below sidebar-last block

If I post to both the home page and to a group page the h2 tag doesn't inherit the "title" class and as a result any three-column page develops a large gap:
http://freire.mcgill.ca/?page=1
On this page the "Go play in traffic" article is crossposted to a group and therefore loses the "title" class. All other content appears after the sidebar-last blocks.
If you return to the homepage you will see this is not a problem with other content.

Hope someone can help!
David