I'm guessing it'll happen during the 2008 May sweeps
A quick Lost timeline:
2005: Michelle Rodriguez and Cynthia Watros are arrested for drunk driving. Their characters are subsequently killed off.
2006: Adewale Akinnuoye-Agbaje is arrested for driving without a license and disobeying a police officer. His character is subsequently killed off.
2007: Daniel Dae Kim begins getting his résumé in order. If he knows what's good for him.