I see what's happening, and it's css related, but it's somewhat hard to describe in words.
Basically you're seeing individual cells on a row "expand" when their content is too big for the cell.
Can you get the same effect in an example? (I'll try here as well).
update -- I've duplicated here, so no need for an example.
And is there any custom.css in your app? If so apply that to the example because it may be something in there causing the conflict.
cheers
Bruce