You want to withdraw the money from your 401K?
If so, you need to talk to the plan administrator, who can help you w/the proper forms and such.
Keep in mind that there will be BIG penalties and interest to pay unless you're of retirement age.
Legally, you don't have to get "permission" from your current spouse to do the withdrawal, but if you split up soon afterwards, then the withdrawal might be considered to be dissipation of marital assets, and you might have to pay him back half of it.
I would need to know more information about your situation.
Hope this helps!