Well after receiving some nice links from Owtobahn, it looks like I'll need to make payroll tax payments on the salary deferal component of my individual 401k contributions I make through my privately held company.
I figure my new employer will cover about 40-50% of my aggregate salary deferal contribution limit to 401ks (defined contribution plans) ($15k), the balance will have to be made through my privately held corp's individual 401k. Self-employment tax adds about 15% (payroll tax times two for social security tax component). It's unfortunate, but a necessary approach to obtain a future tax benefit.
I wonder if you calculated things out, if I'd make back the 15% in over the next 30 years? I assume the capital gains deferal will exceed the 15% cost.