When will they air?

Lost season four doesn't air until February of 2008 in the US. Depending on whether it is moved to Mondays (as has been speculated) it will probably be February 4th or February 6th.There will be three years that will run 16 episodes straight through each year until the series finale in 2010.

http://community.tvguide.com/blog-entry/TVGuide-Ne...

About halfway through this article is when TPTB confirm the February start date...

http://community.tvguide.com/blog-entry/TVGuide-Ne...

And here is an article about the rumors that Lost will switch to Monday nights when it returns.

http://www.buddytv.com/articles/lost/will-lost-mak...

As far as Jericho goes, the seven episodes of the new second season have finished filming, but they are waiting for a timeslot. It could be as early as next month (if something is canceled) or as late as early next year. No official date has been announced. (I'm guessing that they will be smart and leave it until January so they can do a full publicity push.)

http://www.tv.com/jericho/show/58068/new-episodes-...

An interview with TPTB that mentions the tentative January start date...

http://www.tvguide.com/News/jericho-preview-finale...

ETA : Although Sci Fi Wire announced the premiere date as February 6th after their recent discussion with the producers...

http://www.scifi.com/scifiwire/index.php?category=...

lost was on this past wednesday 9 to 10

i dont know about jericho.

:/ sorry.