To study the safety and efficacy of four different doses of Wobenzym (an enzyme combination consisting of pancreatin, papain, bromelain, trypsin, lipase, amylase, chymotrypsin, and rutin) in patients with HIV infection whose CD4 count is between 250 and 400 cells/mm3. To evaluate the effect of Wobenzym on certain surrogate markers associated with progression of HIV disease.