The CPA did spell out a process for determining the common border, but the northern partner rejected the outcome of the commission mandated with researching the subject and presenting their findings. The parties agreed to binding arbitration in the Hague and the process is moving forward. Here's the relevant data:
The SPLM/A and Government of Sudan submitted a second round of arguments to the Permanent Court of Arbitration (PCA) at The Hague, which is tasked with ruling on the dispute over the Abyei Boundaries Commission.
Abyei is an oil-rich area also used by Misseriya and Dinka pastoralists to graze cattle.
The two signatories of the Comprehensive Peace Agreement, Government of Sudan (GoS) and the SPLM, agreed in June 2008, in a roadmap to resolve Abyei disagreement, to refer their dispute to an arbitration tribunal. They formally referred their case to the PCA on July 12, 2008.. . .
The opposing legal teams will now review each other’s arguments and respond with a third written submission to the tribunal on February 28, after which no additional written submissions will be provided unless requested by the arbiters. Oral hearings are then scheduled for April 18-23 after which the tribunal must issue its final decision within 90 days — no later than the end of July of this year.