NEW YORK — The price of oil reached another milestone Monday, jumping to a record inflation-adjusted trading high of $103.95.      

The weaker dollar that has propelled oil and other commodities prices higher sent light, sweet crude for April delivery past $103.76 a barrel on the New York Mercantile Exchange.

That was the level many analysts consider to be the old record high for oil, after its $38 barrel price from 1980 is translated into 2008 dollars.

Futures later retreated from that high to settle up 61 cents at $102.45 after Royal Dutch Shell PLC said it would resume oil shipments from Nigeria that had been disrupted by rebel attacks.

Oil’s most recent run into record territory has been driven by the greenback’s slump against other world currencies. Crude futures offer a hedge against a falling dollar, and oil futures bought and sold in dollars are more attractive to foreign investors when the dollar is falling.

Gold, copper and wheat are among the other commodities that have rallied as the dollar has fallen.

“It’s coming down to another commodity price rally,” said Phil Flynn, an analyst at Alaron Trading Corp., in Chicago.

The dollar has been weighed down by the faltering U.S. economy and the Federal Reserve’s interest rate cutting campaign. Lower interest rates tend to weaken the dollar, which fell Monday to a new low of $1.5275 against the euro.

The struggling dollar has prompted a wave of speculative buying by oil investors seeking a safe haven from the volatility of the stock market. Speculation can become self-perpetuating, driving prices higher and attracting even more speculators.

Many analysts believe oil prices aren’t justified by crude’s underlying supply and demand fundamentals, and are due to fall at some point. Domestic oil inventories are now rising even as a number of forecasters are cutting their demand growth predictions due to the slowing economy.

Late in Monday’s session Shell said it would resume oil shipments from two of its Nigerian facilities that had been suspended under a declaration of force majeure, in which a company says it can’t meet contractual delivery obligations due to events beyond its control, Dow Jones Newswires reported.

Investors are also keeping an eye on OPEC, which meets Wednesday to consider production levels. Most expect the Organization of Petroleum Exporting Countries to hold output steady.

As for where oil goes from here, analyst estimates vary widely, with some predicting an eventual decline to the $65 or $70 range as supplies continue to grow and demand falls.   Others see oil rising as high as $120 as investment capital continues to flow into oil markets from overseas.

For its part, the Energy Department’s Energy Information Administration’s latest prediction is that oil will average $86 a barrel in 2008, up 19 percent from 2007, when oil averaged $72 a barrel.

Surging oil prices are boosting prices at the pump. The average price of a gallon of gas stood at $3.165 Monday, according to AAA and the Oil Price Information Service. That’s down 0.1 cent overnight, but up nearly 70 cents from a year ago. The Energy Department expects gas prices to peak near $3.40 this spring, well above May’s record of $3.227, but some analysts predict prices could rise to nearly $4 a gallon.

Diesel prices, used to transport the vast majority of the nation’s goods, are also surging. Diesel prices hit another new record of $3.674 a gallon Monday.