cash balance plan lump sums

[Gary]

cash balance plan allows for lump sums. Is it true that the lump sum must be greater of acct balance and the value of the account balance projected to 65 using interest credit rate and then discounted to current age using lump sum interest rate. i.e. if interest credit rate is higher than the lump sum interest rate the lump sum would be greater thatn the acct balance?

Also if the interest credit rate and the lump sum interest rate are variable, do you apply the rates in effect at termination and use those in the projecting and discounting?

Look forward to any thoughts on this important subject.