American Telephone & Telegraph Co., New York,...

American Telephone & Telegraph Co., New York, has entered into agreements with several makers of small computers to ensure that its new Unix System V operating system is compatible with the manufacturers’ operating systems. (An operating system controls a computer’s processes.)

The companies are: Microsoft Corp., Bellvue, Wash.; National Semiconductor Corp., Santa Clara, Calif.; Motorola Inc., Schaumburg, Ill.; Intel Corp. Santa Clara, and Amdahl Corp., Sunnyvale, Calif.

Additionally, AT&T; named Microsoft to participate in its pilot Unix System V verification service, which will help ensure compatibility between System V-derived applications.

Pacific Telesis Group, San Francisco, signed an agreement with National Telephone Co. of Spain (Telefonica) to pursue joint ventures in computers, fiber optics, mobile telephones and other voice and data services.

Kaiser Steel Corp., Fontana, said former managers of Myers Drum Corp., which was a Kaiser subsidiary, have acquired certain assets of Myers Drum and its subsidiary, Industrial Molding Corp.

Computer Sciences Corp., El Segundo, said it received a $17.2-million contract from the Colorado Division of Purchasing to serve as fiscal agent for Colorado’s Medicaid program. Computer Science’s government health-services division, Sacramento, will perform the work.

Alpha Pac, a Los Angeles-based distributor of glass and plastic containers, has been acquired by Northwestern Bottle Co., St. Louis, for undisclosed terms.