By Pamela Constable

Washington Post Foreign Service DURBAN, South Africa, Aug. 30 -- A landmark U.N. conference on racism opens here Friday in an atmosphere marred by the intrusion of Middle East politics but uplifted by an outpouring of support from groups ranging from European Roma to Indian untouchables.

More than 7,000 official delegates are expected, including numerous government leaders, and thousands of activists from disadvantaged groups around the world have already poured into this coastal city, promoting their grievances through workshops, media displays and cheerful, impromptu protests inside a cricket stadium near the conference site.

Everyone here is conscious of the keen symbolism of making South Africa the site of the week-long U.N. Conference against Racism, Racial Discrimination, Xenophobia and Related Intolerance. The country institutionalized racial inequality through the white-ruled apartheid system for nearly half a century and has painfully reinvented itself as a free but struggling black-run democracy.

"You are in a country that carries the scars of . . . the abhorrent legacy of the second millennium," South African President Thabo Mbeki said in welcoming the nongovernmental groups earlier this week. The struggle against apartheid in South Africa, he said, was also a struggle against "global apartheid" that must continue worldwide.

Behind the scenes, however, U.N. officials have struggled without success to prevent the conference from being divided and weakened by contentious Israeli-Palestinian politics.

Arab and Muslim countries sought to have the conference declare Zionism -- the movement to establish and promote a Jewish state in what is now Israel -- to be a form of racism and to denounce discrimination and abuses against Palestinians in the territories occupied by Israel. Their campaign was opposed by Israel, American Jewish groups and the Bush administration, which accused Arab countries of trying to hijack the meeting.

The United States succeeded this week in getting some references to Zionism as racism removed from the proposed conference statement, but other language condemning Israel is still included in the draft declaration.

As a result, the administration decided not to send Secretary of State Colin L. Powell to the conference; instead, a low-level U.S. delegation will attend but might not formally participate.

U.N. Secretary General Kofi Annan said today that he had "not given up hope" that the Bush administration would participate, while Jesse L. Jackson, arriving today as a private delegate, said Powell's absence would "isolate" and "discredit" American leadership abroad.

In addition to the Middle East issue, a pre-conference controversy arose over proposals by African countries that the United States and Europe make reparations for slavery. The United States said it would accept language calling for an apology but not for reparations, which could open the door to lawsuits and other demands for financial compensation for long-past wrongs.

Despite the tensions surrounding these controversies, the mood among other conference participants was one of near-jubilant camaraderie, as delegates and activists from dozens of countries and causes discovered one another.

There were groups representing Australian Aboriginals, Iranian Kurds, Quechua Indians from Bolivia and Filipino domestic servants in Hong Kong. Groups opposing the death penalty applauded speeches on the plight of Tibetan refugees from China. Activists opposing the trafficking of Asian women handed out leaflets beside those demanding respect for Roma, also known as gypsies.

One of the most popular groups was a contingent of untouchables from India, also known as dalits, whose cause as the lowest members of a caste-bound society seemed to have been adopted by virtually all the other groups. The government of India tried to prevent the conference from taking up the issue of caste, but the proposed delegates' statement opposes racism on the basis of "work or descent," a euphemism for caste.

"I cannot drink tea from the same cup with an upper-caste Brahmin, because I am considered unclean," said Chandra Angelo, an untouchable woman from southern India, swaying slowly to a drumbeat as she held a protest poster.

Annan met with the nongovernmental groups at the stadium here today and politely tried to lower their expectations for the conference and its final documents, in which gaining international consensus inevitably will require losing much of the sharper language and demands for redress of grievances. At several points, he was booed or shouted down by frustrated activists.

"Many of you, I know, feel your concerns are not properly represented in the conference," Annan said. "But your anger and frustration can be valuable in themselves. . . . The important thing is not the degree of formal recognition you achieve in the conference hall, but what you do when you get back home."