Sorry but you don't "one-up" your opponent and then cry cease fire.
That would be like me coming up uto you hitting you with a bat, then saying "cease-fire" and then blaming you for retaliating.
Al'Jazeera reports (FWIW) that Hamas did not agree to this ceasefire:
Al Jazeera English - Middle East - Olmert announces Gaza ceasefireDespite Israel's self-declared ceasefire, Hamas officials said they would not stop fighting until Israeli troops withdrew. "If the Israeli military continues its existence in the Gaza Strip, that is a wide door for the resistance against the occupation forces," Osama Hamdan, a Hamas official in Lebanon told Al Jazeera. Fawzi Barhoum, a Hamas spokesman in the Gaza Strip, said: "The Zionist enemy must stop all its aggression, completely withdraw from the Gaza Strip, lift the blockade, and open the crossings. We will not accept the presence of a single soldier in Gaza."
If I was a leader in some same predicament I would not want any confusion. If a rocket went off towards Israel then I would want to know if it came from men under my control, men not under my control, or maybe possibly even the "enemy" seeing as they are actually their.
And just to crush this now. No I don't personally believe that Israel has been firing the rockets at themselves also. And it is a situation that you would never want to happen.
Is society was made of coral our world would be floral.
When Israeli settlers enact violence on Palestinians, without cause, Israel does not just ignore things, as Hamas does.
"Never fear. Him is here" - Captain Chaos (Dom DeLuise), Cannonball Run
Mace Windu: Then our worst fears have been realized. We must move quickly if the Jedi Order is to survive.