The truce with Sudan is holding, largely because the Sudanese government is concentrating on the threat to their oil fields in the southern part of Sudan. There, the southern (black African) rebels are threatening to declare independence, and try to take some of the oil with them. The fight in southern Sudan, like the one throughout Chad, predates the oil. It's all about culture. The northern Sudanese, and many Chad tribes, consider themselves Arab, and thus superior to other tribes that simply consider themselves African. The "Arab" tribes have had generations of close relationships with Arabs from the north, and many speak Arabic, as a primary or secondary language. That makes them believe they are Arab, because otherwise they appear to be black Africans. In Islamic culture, Arabs are accorded extra respect, because Mohammed the Prophet was an Arab, as were most of the early leaders of Islam. But many Arabs today consider Arab Moslems superior to non-Arab Moslems. This attitude is not shared by most non-Arab Moslems, and it causes friction and, in places like Sudan and Chad, and lots of violence.
Although Chad and Sudan have restrained the rebel groups they host, from raiding across the border, banditry and crime is a growing problem among the half million refugees in eastern Chad. There are not enough police (who are often corrupt anyway) or peacekeepers, to deal with the problem. The foreign aid workers issue reports on the problem, but these rarely make headlines.
The Oil Curse is alive and thriving in Chad. In most nations, especially non-industrialized ones, oil revenue triggers an orgy of corruption and the government becomes dominated by tyrants more interested in stealing, than in running the nation efficiently. Despite strenuous international efforts, the Chad government has stolen or squandered most of the oil money. For the last three years, the government has had over a billion dollars a year in oil revenue. Most has gone to pay for the rulers lavish life style, and to maintain a large security force to prevent any other group from grabbing control of the government, and the oil. Loans made by international groups, to pay for building the oil infrastructure, are going unpaid (although loans to oil companies, who run the operation, are repaid, because otherwise the oil production would stop). The poor get nothing, while the guys with guns and power get everything.