I can give you some general advice, but it would be helpful to know more about your situation.

First, let me say, you did the right thing. The whole point of accounting is to verify the accuracy of financial statements. The irony is that while everyone wants to know when they re-being cheated, no one likes a tattletale. So, instead of seeing you as a someone who uncovered wrongdoing, it’s entirely possible that you’ll be viewed as a troublemaker. You’re right to worry about how to handle this. Be honest with your new employer, but don’t get into the gory details. The right attitude is that what you did is just part of the job -- call it the "Dragnet" Joe Friday approach.

If you want more specific advice on how to handle your individual situation, come over to the Finance Board and re-post your question there. Please add more details about what happened at your old firm. At worst, the accountants who post on the Finance Message Board will share your pain, and at best,  they' ll help you form answers for each of those questions.