ADOBE <ADB>, HIGH PLAINS <HPOC> TO MERGE Adobe Resources Corp and High Plains Oil Corp said they reached an agreement in principle under which High Plains will be merged into a unit of Adobe. Under terms of the agreement, the companies said each share of High Plains common stock not owned by Adobe or held in the High Plains treasury will be exchanged for 1.12 shares of newly issued Adobe common. The exchange, they said, will be made on the effective date of the merger, which must be approved by both companies' boards and High Plains' shareholders.