IT is only a month since the government and rebels in Indonesia’s tsunami-struck province of Aceh signed a peace deal to end one of Asia’s longest running wars. Although both sides appeared genuinely committed at the time to the deal, and the people of Aceh overjoyed, there was nonetheless a worry that it might fall apart like previous peace attempts. Would the government pull out its forces as promised? Would the rebels hand in their arms as agreed?

So far the wheels are turning as planned. Both sides are sticking to their part of the bargain. Just a week after the deal was agreed, the first Indonesian troop withdrawal took place; more than 1,250 soldiers stationed near the second largest city in the province, Lhokseumawe, were pulled out. Five days ago, 1,300 members of Indonesia’s elite mobile police brigade left for the capital Jakarta. And on Thursday, members of the Free Aceh Movement (GAM) started handing in their weapons.

But it could still go pear-shaped. The last peace deal broke down during the delicate decommissioning period, and it could again. There is a great deal of mistrust between the two sides. That is hardly surprising. After 29 years of conflict in which 15,000 people have died, the bitterness and suspicion are not going to vanish overnight. There is a real danger that they could provoke one side or the other into a course of action that undermines and destroys the deal. GAM, for example, is supposed to hand in a third of its arms by tomorrow. The total figure has been set at 870 pieces of weaponry — not a lot for such a bloody war. But by the end of the first day, only 78 pieces has been handed in.

There is also confusion about the number of Indonesian troops and police who will be pulled out and the number that will remain. Figures for those leaving vary between 6,000 and 22,000 depending on who you are talking to. It is not deliberate deception; it is poor communication, plus a lack of clear-cut information on the number of troops actually in the province. The trouble is that this could be seized on by some of the rebels to slow down the arms handover, with potentially disastrous results. There is already disquiet within GAM over Indonesian government plans to keep between 21,000 and 23,000 security forces in the province after the pullout, a figure they say is too high. Another potential destabilizing issue is GAM’s claim that there are still 10,000 pro-government militiamen in Aceh who plan to attack the rebels after disarmament. The claim may be true; it may not. But the rebels believe it. Jakarta is going to have to show either that there are no militiamen, or that they have been likewise disarmed. Neither will be easy.

The potential for a spanner in the works is serious. The path to peace is precarious. Only at the end of the year will anyone be able to judge it a success. Caution has to be the watchword. But it is optimistic caution. The process may be fragile, but it is working. For the people of Aceh who have suffered so much, there is reason for real hope.