Does a change in Adopting Employer's Corporation constitute a plan termination?

[Guest spanarkle]

This Corporation was a Missouri Corporation, it established a 401(k) plan and now, a few years later, decided it wanted to Incorporate under the laws of Delaware. The employer has not changed employees, addresses, phone numbers, or anything else; only their taxpayer identification number. Can a simple amendment to the 401(k) plan adoption agreement, amending the Adopting Employers EIN handle this, or is it necessary to go to the extreme of terminating the plan, giving th employees distributions and letting them decide whether they want to roll into the plan of the new employer?