The extraordinary breakthrough inthe troubled inter-party negotiations came when ZANU-PF negotiators hadto accept that the version of the political agreement signed onSeptember 11 was a valid document designating the post of primeminister for MDC leader Morgan Tsvangirai.
The amendment,signed off on by the six negotiators, page by page, now has to be giventhe green light by the three parties' principals who are all presentlytravelling internationally.
However, constitutional experts saythere is nothing to stop Morgan Tsvangirai from being sworn inimmediately as prime minister, should he wish that.
Mr.Tsvangirai defeated Mr. Mugabe in the presidential election in March.The second round from which Mr. Tsvangirai withdrew becuse of violenceagainst his supporters was not recognized by any regional governments.Mr. Tsvangirai's MDC has a small parliamentary majority.
If theprincipals agree to the draft amendment it will then be published and amonth later debated in parliament and it will need a two-thirdsmajority, and President Robert Mugabe's signature, to become law.
If there are no obstacles, lawyers say, a unity government could be in place at the earliest by January 15.
The amendment closely follows the original political agreement signed in September.
Mr.Mugabi is currently at a United Nations meeting in Qatar. Mr.Tsvangirai is in Morocco collecting a human rights prize and Mr.Mutambara is in the United States, on a private visit.
FormerSouth African president Thabo Mbeki presided over the mediation inSeptember which created the post of prime minister for Mr. Tsvangirai. Mbeki was appointed by the Southern African Development Community toestablish dialogue between the rival parties. His negotiating teampresided over this week's breakthrough negotiations in South Africa.
NelsonChamisa, spokesman for Mr. Tsvangirai's MDC said despite the agreementthere are still matters outstanding. SADC officials have acknowledgedthat there will have to be further negotiations to fairly allocate thepositions of 10 provincial governors after the inclusive government issworn in.
Nevertheless there is some relief on the streets ofHarare over this tentative agreement. There had been growing regionalpressure on the parties to end their disputes and focus on trying tosolve Zimbabwe's humanitarian and economic crises.