(repeats to correct spelling error in paragraph 6)

By Skye Wheeler

JUBA, Sudan, Aug 1 (Reuters) - Sudan's national census, central to the success of democratic elections and a referendum on secession for oil-rich south Sudan, may be postponed a second time, a census official said on Wednesday.

The census, which South Sudan President Salva Kiir says is the region's first true population assessment, has already been put off from mid-2007 to January 2008 because of funding problems.

But the joint north-south body in charge of the census process said it was recommending delaying the count until February next year because January was unsuitable.

The January 2005 peace deal that ended Africa's longest civil war paved the way for democratic elections by 2009 and gave southerners the right to decide by 2011 whether to secede or remained united with the north.

Members of the body running the census said teachers, needed to help with the count, would still be working in January.

"January will also coincide with the pilgrimage, haj, an important religious occasion that cannot be overlooked," said Isaiah Chol Aruai, head of the Southern Sudan Commission for Census, Statistics and Evaluation.

The central government is supposed to pay the $54 million cost of the census, but Aruai said it had committed itself only to contributing $30 million, to be paid in equal monthly instalments between June and September.

"But for June it has not yet been fully paid and for July we've not yet had anything," said Aruai, adding it was still unclear how and when the remaining $24 million would be paid.

The census body received only $5 million in January-June this year, and Aruai said this was 'roll-over' money which was not paid last year.

Funding delays meant a south Sudan pilot census, due in 2006, was not carried out until April this year, and results are not yet available. "We are supposed to plan based on these results," said Aruai.

In addition, the more-developed north of Sudan has almost finished updating its maps, while much of the south had to be mapped from scratch and less than half was complete, said Aruai.

Floods across south Sudan caused further mapping delays.

The International Crisis Group, a thinktank, said in a report this month that the census was a crucial part of keeping the peace between north and south Sudan. It blamed the north's dominant National Congress Party for the funding delays.

The 21-year north-south war, complicated by issues of religion, oil, ethnicity and ideology, killed 2 million people and drove some 4 million from their homes.

AlertNet news is provided by