I exceeded 2009 ira contribution limit, what do i need to do?

i mistakenly made two contributions to both a traditional ira and roth ira that put me over the $5000 limit. i know i will pay a penalty and i need to w/d the execess amount plus any earned money on the execess. who calculates the earned money, me (most likely) or the bank and does it have to be exact? it has been in a mm fund so it will only be a few dollars at most.