safrank99 - CPA here, so I have to give you the correct answer. Get your next accountant to file an amended return for 2008. The IRS has 3 years to pull your return and audit. There are programs that look for statistical anomalies and depending on what was overstated to cause the refund you may have a higher than average chance of being detected. In short it is easier if you clean it up now rather than the IRS bringing it to your attention 2 years from now. You can also do it yourself if you would like, go to IRS.GOV and get a 1040X, don't forget about amending state and local returns as well.
Get my e-mail from Jack if you have any questions.