Is it possible to withdraw your admissions from a UC and enter a cal state in the spring ?

I was supposed to enter UC Irvine in the fall of 2010 but due to financial reasons i feel that this is no longer my best choice..Is it possible to withdraw my admissions decision and enter a CSU in the spring instead?( without having to reapply to the csu since i was accepted to the fall term, or would i have to reapply to the spring term?)