what do you do if the problem goes back more than 6 years or for years that the sponsor does not have records. for example, lets say you only have records for the last 6 years but you know the plan was administered the same way the entire life of the plan and you don't have records for any years beyond 6. how can you determine the contributions? should you even include those years in your submission?

I'd first try to earlier appropriate documents form other sources, if possible--the current or prior TPA, Trustee or custodian, or the employer's CPA or attorney. If this fails, I'd apply for VCP correction for the years for which you have good records, and indicate in the application that you are making corrections as far back as records are available and that, if the correction is approvied by the IRS and you later obtain documentation for prior years which also shows the same errors, you will make a comparable correction for those years, as well.

it seems reasonable. i just dont want to open a can of worms.

Well, then you just have to choose whether to make the suggested correction or decide that it's better to make no corrections at all, or to make the corrections without mentioning prior years (after all, the IRS only investigates what's in front of it and makes no assumpitons about prior or other years). It's just your typical risk/benefit analysis without all the facts . . . !!

Or, better yet, go in under the "John Doe" VCP process and mention the earlier years. Then, other than the IRS fee being lost, you risk little--just the normal risk of potentially doing nothing--but, if the IRS says that it will not move without all prior years, then just withdraw the application.