Good grief. I had no idea that it was open ended.
In that case, I'd highly consider negotiating to have him sign away his rights. How does the calculation for spousal support work? Would it be a significant amount that you'd have to pay monthly? Also, keep in mind that alimony is tax deductible, at the very least. I'd talk to a CPA to do a risk vs reward analysis on present vs future values of paying him off now vs paying spousal support for 9 years.