According to news accounts, Graves has been ill since a trip to Germany in February but only recently let it be known that he has been a patient at the Kessler Institute for Rehabilitation in West Orange. His lower body is paralyzed and doctors are uncertain whether his condition is permanent, he has told reporters.
Graves, 68, had an unidentified illness -- possibly meningitis -- that began as a sinus infection but went on to attack his nervous system including his spinal cord.
He spent six weeks at New York-Presbyterian Hospital before being transfered to Kessler in early April.
Graves has said he has kept up with his work, which ranges from a line of housewares for Target stores to buildings for the U.S. Department of State, a Manhattan skyscraper, and the headquarters for Team Disney in Burbank, California.
At NJIT Graves' Laurel Hall North and South house 300 students. The five-story T-shaped building, colored in Graves' signature palette of muted turquoise, orange, and gold, opened in August, 2001.
Graves taught at Princeton University for 40 years. In 2001 he was awarded the Gold Medal of the American Institute of Architects, one of the profession's most coveted honors.