OBJECTIVES: I. Determine the maximum tolerated dose of oral BIBX 1382 in patients with solid tumors. II. Determine qualitative and quantitative toxicities of oral BIBX 1382 in these patients. III. Determine predictability, duration, intensity, onset, reversibility, and dose relationship of the toxicities of oral BIBX 1382 in these patients. IV. Determine safe and optimal doses of oral BIBX 1382 for a Phase II study. V. Assess the pharmacokinetics of oral BIBX 1382 in these patients. VI. Document any antitumor activity in these patients treated with oral BIBX 1382.