Unreported Income
Where a taxpayer has failed to report income, including foreign source income, and voluntarily reports it, only the tax owing on the unreported income plus interest on it will be charged.
That came from
http://www.taxpage.com/Articles/DISCLOSURE.htm - not sure how accurate it is I just found it thru google.
Bottom line is you have to pay taxes. They may waive the fees and interest if you voluntarily come forward but do that thru an atty.