Today's "volunteer" Army is looking for more than volunteers.

For the first time in nearly three decades, the Army is searching out military retirees - especially those with medical skills - and forcing them back into uniform.As the buildup of U.S. forces in the Persian Gulf surges toward the 400,000 level and the United Nations deadline nears for an Iraqi withdrawal from Kuwait, the Army is digging deep into its personnel rec-ords for help in supporting the force.

Lt. Col. Henry H. Hanrahan, an Army planner, said Monday that an initial call-up of 15 retired physician assistants was approved last week, and about 200 other retirees probably would be involuntarily recalled for active duty over the next month.

It is the first involuntary use of Army retirees since the 1961 crisis over East Germany's erection of the Berlin Wall.

Hanrahan said that about 4,000 Army retirees have volunteered for duty in the gulf crisis but that involuntary call-ups were needed because there aren't enough volunteers with the skills needed most. The Army is especially eager to get more medical specialists in uniform.

About 150 volunteers have been put on active duty, and about half of those are performing medical duties in support of Operation Desert Shield, Hanrahan said. Approximately 300 more volunteers are likely to go on active duty over the coming month, he said.

Retired military officers aren't required to maintain any active association with the services. But a service secretary has the authority to force retired personnel back into uniform if it is deemed necessary for national security.

The Army's increasing need for medical skills reflects a broader trend within the U.S. military as tens of thousands more American troops are deployed to Saudi Arabia and the Jan. 15 United Nations deadline approaches for Iraq to withdraw from Kuwait.

The Navy last week disclosed that it is deploying two additional 500-bed mobile support units.

The Navy announced Monday that 769 Navy Reserve members, including many medical specialists, are being ordered to active duty.