If the combined values of your foreign bank accounts exceeded $10,000 at any time during the year, you have to File Form TDF 90-22.1, Report of Foreign Bank and Financial Accounts.
Form TDF 90-22.1 for 2006 has to be filed by June 30, 2007. Extending the tax return of the individual doesn't result in an extension for filing the Form TDF 290-22.1, and no separate extension is available for filing the form.