According to Gershon Baskin of the Israel / Palestine Center for Reaserch and Information, officials of Hamas, the Palestinian Authority and Israel are working behind the scenes and through intermediaries to put a ceasefire in place in Gaza. He writes on his organization's Facebook page:
If the ceasefire holds all night long it will be formalized tomorrow - lots of work behind the scenes, several hundred sms's and phone calls during the past 48 hours - and a lot of trust between people who wanted this to happen.
Hamas has sent a message to the Israelis - they are making serious efforts to control and stop the fire. Hamas leaders Haniyeh and Mashal have informed all of the leaders of the various factions that anyone shooting rockets into Israel will be stopped and arrested and even Ahmed Jaabri the head of Ez el din Qassem forces has deployed his men all over Gaza to stop the rocket fire.
I was the person who sent the message to the Israelis - it went to Bibi, Barak, Yoram Cohen, Beni Ganz and others.
IPCRI - Israel/Palestine Center for Research and Information
UPDATE (8/22/2011 3:40 AM):
Gershon has posted that he
will be on IBA (Israel Broadcast Authority) English news today (i.e. Monday, August 22) on their 5pm news program talking about Gaza, Hamas, ceasefires, September, etc.