Why is it a different issue though?
Israel captures terrorists who shoot at cars. It imprisons them. Then, in an attempt to change the atmosphere, it frees them as long as their gunshots cracked the windshield or blew out the tires but didn't hurt the driver or passengers.
After all of this has been negotiated. the Palestinian Authority announces that the Prime Minister himself has condemned three people accused of working with Israel to stop the terror -- which the Palestinian Authority agreed to do as the first step of the so-called Road Map to peace!
I think that they are exactly two sides of the same coin. Unfortunately, for Israel the coin is "heads I win, tails you lose."
There is a difference. The people that Israel is releasing are Palestinians, not Israelis. The ones that the PA is going to execute are Palestinians. They are not Israelis. You would have a case if they in fact were Israeli citizens planted as spies but no they are traitors. And just like that American Jew who betrayed the US to the Israelis (and the Russians) they should at the least remain imprisoned for life.