A few questions on the design of tables

Hi all,

My project porting my application has been sidelined a bit because Vaadin's tables don't have some functionality we need. Essentially it comes down to the need for footers (for which there's already a ticket slated for 6.4.0), cells that span multiple columns and the ability to include what Vaadin is calling "header" and "footer" rows anywhere within the table.

My company is willing to spend some time implementing a new Table component that meets our needs, and potentially contributing it, but I'm wondering if perhaps our 2nd requirement wasn't included for some technical reason. I'll be learning as I go should I have to re-implement tables... So I thought I'd ask =)

Reading over Vaadin's table implementation, I can't see any reason why this wouldn't be possible technically, but I'm no expert. Thoughts?