The theme of the reformed sinner has provided inspiration for religion, literature and film alike.

On Wednesday, it was the turn of the markets to cheer the adoption of a hair shirt, by Greece, which announced an austerity package viewed as, well, austere in the face of its sovereign debt crisis.

Athens unveiled a pension freeze, a 30% cut in some bonuses to public sector workers, a two point increase in the top rate of VAT and higher levies on cigarettes and alcohol among measures aimed at raising an extra E4.8bn this year.

The response was one of relief on markets, manifested in firm shares, a rebound in the euro, and oil touching its highest for getting on for two months.

Sterling made ground too, on data showing strong service sector expansion, helping a drop in the dollar of more than 0.7% - good news for prices of US exports such as food commodities.

Bear retreat 

In Chicago, it was the grains which benefited most, with wheat leading the charge as investors, who have bet large on further price drops, scrambled to cover positions.

"A big drop in the US dollar has prompted a large amount of short covering in the grain market," Darrell Holaday at broker Country Futures said.

March wheat ended 2.3% higher at $5.03 ½ a bushel in Chicago, with the May lot up 2.2% at $5.15 ½ a bushel.

That gave a leg up to corn, in addition to the boost provided by rising oil. Nearly one-third of US corn is processed for energy at US bioethanol plants, so crude prices are a major influence.

And that's before factoring in expectations of a drop of 50m-60m bushels in the US Department of Agriculture's 2009-10 corn production estimate, when fresh data are released next week.

Corn alert 

Then, of course, there are the lingering concerns of a damp US spring, and hampered corn planting, ahead.

"Wet weather is forecast in the US Midwest the first half of next week, which increases fears of a wet spring," Vic Lespinasse, GrainAnalyst.com analyst, said.

"Worry about a wet spring could lend support to the corn market as less corn would be planted if the weather delays planting."

Corn for March closed 5.25 cents higher at $3.75 ¾ a bushel, with the May lot adding 5.25 cents to $3.86 ¾ a bushel.

Struggling soy

But what's good for corn prices is being to a large extent poor for soybeans.

Dampness "would also be bearish for beans as wet spring conditions could force farmers to plant more beans instead of corn", Mr Lespinasse added.

Soybean bulls might be grateful for wet in South America too, hindering the harvest of huge crops which have for months hung over US prices.

"Weather conditions in South American are offering a floor under beans as rains delay harvest in Brazil and raise quality concerns in Argentina," broker Benson Quinn Commodities said.

Soybeans edged 0.25 cents higher to $9.54 ½ a bushel for March delivery, with the May lot ending unchanged at $9.63 ½ a bushel.

Softs slip 

Wheat's gains were reflected in Europe, with some dilution to account for the strengthening pound and euro.

Paris wheat for May ended up E0.75 at E124.25 a tonne, with its London counterpart crawling £0.10 ahead to £96.55 a tonne.

However, the weaker dollar failed to pull cocoa and sugar out of the grumps. Raw sugar for May closed down 0.59 cents at 22.05 cents a pound.

May cocoa slid $6 to a six-month low of $2,823 a tonne in New York, and by £9 to £2,145 a tonne, a three month bottom, in London.