* Robusta moves lower, hovers above six-month low
* Arabica climbs after one New Jersey warehouse reports damage
* Ivory Coast customs officials block cocoa products exports
(New throughout, updates prices; adds analyst comment, second byline/dateline)
NEW YORK/LONDON, Nov 2 (Reuters) - Cocoa futures climbed on Friday, passing above technical support levels and bucking weakness in other commodities, as some exports were blocked and purchases in the main West African growing region were slow.
Arabica coffee futures were quietly higher after one New Jersey warehouse reported water damage following Hurricane Sandy, while robusta and sugar eased.
The Thomson Reuters-Jefferies CRB index, a global benchmark for commodities, tumbled more than 1 percent to a 3-1/2-month low as the U.S. dollar rallied to a three-week high versus the euro and a gauge of business investment plans showed lackluster momentum in economic recovery.
ICE December cocoa was up $21, or 0.9 percent, at $2,441 per tonne by 12:42 p.m. EDT (1642 GMT), as traders kept watching early progress of main crop harvests in West Africa. The market climbed for the second straight day after hitting its 200-day moving average around $2,352.
Benchmark Liffe March cocoa futures were up 17 pounds at 1,577 pounds per tonne, extending gains above the 200-day moving average around 1,536 pounds.
In Ghana, the world's second-biggest cocoa producer, cocoa purchases hit 86,028 tonnes by Oct. 19 in the first week of the season, down 42 percent from the same period a year ago, Cocobod data showed on Thursday.
Dealers said the number was lower than expected and was helping to underpin the market.
``People are looking at recent Ghana purchases which are further behind last year, but we have to compare apples to apples - considering the overflow from previous season, purchases in the first week of last year would have been very strong,'' said a London-based broker.
Weak purchase figures, if maintained, may indicate production may reach the level expected when Ghana embarked on its pre-harvest sales program, raising the possibility the world's number two producer may have oversold its crop.
Across the border in the world's biggest grower, Ivory Coast, customs officials blocked the export of 72,000 tonnes of cocoa products from the recently-ended 2011-12 season due to confusion over tax rates, exporters and customs officials said.
This, combined with an outbreak of fungal black pod disease in Ivory Coast, could push up prices, dealers said.
``It could well do (provide support) as it's 72,000 tonnes. There is so much bullish news at the moment it's hard for the market to go anywhere but onwards and upwards from here, in the short term anyway,'' a UK-based broker said.
Arabica coffee futures also climbed, after an exchange-certified New Jersey warehouse reported to ICE that it experienced water damage from Hurricane Sandy, causing 35,000 60-kg bags to be flagged as non-deliverable until further notice.
``It's probably seeing some buying off those reports but the market's being cautious,'' said Steve Platt, analyst at Archer Financial in Chicago.
``There's a lot of uncertainty with regard to the level of damage. At the same time, the market's been in a technically weak state.''
December arabica coffee futures were up 1.15 cents, or 0.8 percent, at $1.5460 per lb. The contract hit $1.5280 on Thursday, the lowest level for the front month since June 22.
``It's just a technical bounce as prices have fallen quite sharply this week, below the $1.65 mark. At these levels it could be some bargain hunting roasters adding coverage,'' Macquarie analyst Kona Haque said.
The December/March spread widened to around a 5-cent discount, a 1-1/2-year high as spreading took place, weighed down by the increased penalties for aged certified beans.
Robusta coffee futures on Liffe were little changed in an inside session, with prices holding above a six-month low set earlier this week as the focus remained on Vietnam's crop which is expected to be large but slightly below last season.
January robusta coffee futures fell $5, or 0.3 percent, to $1,979 a tonne. The contract touched $1,965 on Wednesday, the lowest level for the second-month since April, under pressure from ample Vietnamese supplies.
``Even the cash prices in Vietnam are coming off and so (Vietnamese) production is having an impact on futures markets as well. I think there could be some downward pressure as we're only just at the beginning of the harvest,'' Haque said.
Raw sugar was little changed in choppy dealings, its second straight inside session as the market lacked new fundamentals.
March sugar futures were up 0.03 cent at 19.41 cents a lb as the market continued to consolidate just above a six-week low set earlier this week at 19.18 cents.
Dealers said an anticipated substantial global surplus in 2012/13 was keeping the market on the defensive while producers now appeared to be willing to sell at lower prices.
December white sugar on Liffe dipped $3.10, or 0.6 percent, to $535.50 per tonne.
(Additional reporting by Nigel Hunt in London; Editing by Alison Birrane, David Cowell and David Gregorio)