IRC §448 discusses which business entities can and cannot use the cash method of accounting.  C corporations, partnerships with C corp partners and tax shelters are prohibited from using the cash method UNLESS they meet the gross receipts requirements of 448(C).  This doesn't apply to S corporations because C corporations can't be S corp shareholders; neither can partnerships.  So there is no need to pass this information through to the shareholders.  I think this is a LaCerte error and needs to be fixed.