It sent a jolt of delight through me. A small crowd had gathered to look. A garbage truck. Men in orange Harare city council overalls, shovelling into it heaps of fly-blown, stinking, rat-infested refuse that had been accumulating for about five years.

The next happy shock was the dozen men and women in reflective yellow vests with machetes, hacking down the 3m elephant grass on the road verge. And lo, nearby, were four shiny new tractors with mowers, turning a suburban eyesore of rank, mosquito-laden weed into parkland.

And then there was the glory of freewheeling down the steep slope to the West Road traffic lights and encountering a team of council workmen next to a trailer exuding the delicious aroma of hot tar. It was like a ballet as they patted and stamped gravel and bitumen into the potholes that had cracked the sumps and buckled the rims of hundreds of vehicles.

There have been only rare glimpses of the Harare council maintenance department since 2000. But Zimbabwe's power-sharing marriage is just over five weeks old and, to everyone's surprise, it has made an electrifying difference. Suddenly, up there and running the Government, alongside the malevolent and apparently indestructible President Mugabe, is Morgan Tsvangirai, the Prime Minister and champion of the people.

His first move was simply to dump Robert Mugabe's joke currency and allow US dollars and other convertible currencies to circulate freely. Immediately it unjammed a multitude of cogs in the nation's stricken engine. The infusion of just a little real money has enabled the Harare city council to make a modest start on the worst of the decay left by the shameless Mugabe, his ministers and officials.

It has brought sporadic life to my home telephone after years of dead silence. The dialling tone, when it comes, still gives me a little shudder of pleasure.

The long, anxious bread queues outside the Greek store up the road are gone and the empty shelves, which Iannakis tried to disguise with cabbages six weeks ago, are filled with eggs, cigarettes, fruit juices, milk, soap, sausages, chocolate and any kind of beer you want. So fast have the US dollar and the South African rand become established in the past five weeks that he can usually give change in notes and sometimes even coins, instead of handing out boiled sweets or bananas in lieu of cash.

Best of all, his irregular, elderly heartbeat no longer has to bear the panic of central bank inspectors descending on the shop to catch him illegally selling his paltry merchandise for real money, and squeeze out a bribe to look the other way.

And prices are dropping as goods abound and competition asserts itself. “I bought sugar for US$1 for a kilo, half of what it cost me in January,” said Langton, who works as a gardener down the road. “Bread and mealie meal are cheaper now. It is all because of PM.” You mean the Prime Minister, Morgan Tsvangirai? I asked. “PM means Papa Morgan,” he said. It was a touching endearment, such that Mr Mugabe could never hope for.

Other windows are opening too. With a lump in my throat, I walked into the lion's den last week and presented myself at the main government office for an interview with Mr Tsvangirai's Finance Minister, Tendai Biti. Six weeks ago the receptionist would have summoned a pair of wolfish spooks to deal with a brazenly white journalist. Now the man politely showed me the way.

I visited a friend, an aide of Mr Tsvangirai and long on the Central Intelligence Organisation's hate list. I was surprised to see him working with stationery bearing the official coat-of-arms of the Zimbabwe Government. An arrest warrant would have been the only official document he was allowed to see before.

On the day that Mr Tsvangirai's wife Susan was buried, I was behind a minibus and watched the conductor stick up an MDC poster on the back window. Not long ago it would have got a brick through it.

January promised another black year of misery and despair under Mugabe's brutal failed state, but the presence of Mr Tsvangirai and his colleagues in the new Government has provided a sunburst of hope for Zimbabweans, as they seize on the marginal changes that have acquired such highly charged significance.

The sense of optimism is alive, but after the repeated violent destruction of expectations of the past decade people have also learnt to recognise the fragility of their hope. It's like walking into a pool of delicious, cool water while knowing that broken glass lies on the bottom.

“Nothing has changed,” Mr Mugabe said during his grotesque 85th birthday celebrations last month.

Ask Israel, the rose vendor, who last week had to flee from police raiding “illegal” traders outside the nearby supermarket. Their sole purpose was to steal the goods that the traders abandoned.

Or the young man in Tongogara Avenue who took too long to pull to the side of the road when the president's 25-vehicle motorcade went hurtling past last week and got the usual treatment - he was dragged out of his car by one of the escort's soldiers, then kicked and beaten with a rifle butt in front of scores of onlookers.

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