Shas has publicly declared that as soon as the government starts talking about Jerusalem they will leave the government. In the meantime, they are maintaining the fiction that such talks are not going on.
It is clear to everyone that such talks are being held in secret (or not so secret).
Sha's strategy is to stay in the government as long as possible and squeeze as much money out of Olmert as possible. There is no question this i working (in terms of teh money). However, this is a very dangerous strategy. A very likely result will be that the government will be presented with a fait accompli regarding the secret negotiations over Jerusalem. Shas will leave, but it will be too late, the damage will have been done. Shas is also risking a lot politically. Most of Shas's voters are traditional Sefardim who are generally right wing. If Shas is perceived as allowing Olmert the time to divide Jerusalem they will pay dearly at the ballot box.