* All four trucker unions sign deal
* Three-week strike had caused fuel, cash shortages
* Rand firms after announcement
(Updates with signed deal, other strikes)
By Wendell Roelf
CAPE TOWN, Oct 12 (Reuters) - South African truck drivershave signed a wage deal to end a three-week strike, the freightemployers group said on Friday, putting an end to a walk-outthat has hit deliveries of fuel, cash and consumer goods inAfrica's top economy.
More than 20,000 truck drivers have taken to the streets inoften violent protests since late September, demanding higherwages. At least one person was killed and dozens of trucks weretorched by demonstrators.
"The agreement has been signed by everyone. The strike isoff immediately," Penwell Lunga, chairman of the Road FreightEmployers Association told Reuters.
He said workers have agreed to accept wage increases of 10percent from March 2013, 8 percent the following year and 9percent for 2015.
All four transport unions were part of the agreement, RFEAspokeswoman Magretia Brown-Engelbrecht said, although she didnot reveal details of the deal.
News of the wage deal helped relieve some of the pressure onthe rand . The currency, which tumbled to a 3-1/2 yearlow on Monday on concerns about weeks of crippling strikes, hitits highest in a week immediately following the news.
Since August almost 100,000 workers across South Africa -including 75,000 in the mining sector - have downed tools inoften illegal and violent strikes that have undermined investorconfidence and already shaky economic growth.
Moody's also cut South Africa's credit rating last month,citing the government's failure to tackle the industrial unrestthat has swept from the platinum and gold sectors into otherparts of the economy.
In the diamond industry, striking workers at Petra Diamonds
mines have agreed to return to work while union leaderscontinue talks with management, the National Union ofMineworkers said on Friday.
Petrol stations have been experiencing delays of up to a dayin getting fuel and some have run completely dry, the SouthAfrican Petroleum Industry Association said on Thursday.
Other affected companies include logistics groups ImperialHolding , Super Group , Grindrod ,Barloworld and Bidvest .
More than 50 people have been killed in labour-relatedprotests in the last two months, including 34 shot dead bypolice at Lonmin's Marikana platinum mine onAug. 16.
South Africa is home to 80 percent of known reserves ofplatinum and the price of the precious metal has risenmore than 20 percent since the Marikana shootings, the bloodiestsecurity incident since the end of apartheid in 1994.
Striking gold miners rejected the industry's latest wageoffer on Thursday. Africa's top three bullion producers -AngloGold Ashanti , Gold Fields and HarmonyGold - have given them until Monday to reconsider.
In a separate dispute, a union representing 190,000government workers has threatened a nationwide strike from nextweek. One of the union's provincial branches will meet withemployers on Tuesday to discuss the workers' demands.
Around 3,800 clothing workers have also downed tools overwages, the Southern African Clothing and Textile Workers' Union(SACTWU) said.
(Additional reporting and writing by Agnieszka Flak; Editing byDavid Dolan and Jon Hemming)
Keywords: SAFRICA STRIKES/TRUCKS