This is a phase I study using an accelerated titration design to determine the maximum tolerated dose (MTD) of capecitabine given orally on a BID schedule from days 1-14, in combination with docetaxel given at a fixed dose of 75 mg/m2 IV on day 8. Once the MTD of capecitabine has been determined, an additional nine patients with accessible tumors will be treated at the MTD. Pharmacokinetics of plasma capecitabine, 5-FU, 5'-deoxy-5-fluorouridine, and docetaxel will be assayed in these nine patients, and tumor biopsies will be taken to assess Bax:Bcl-2 ratios and Bcl-2 phosphorylation at several time points. The primary aim of this study will be to determine the maximum tolerated dose and dose limiting toxicities of capecitabine when given with a fixed dose of docetaxel on day 8 of a 21 day schedule. Secondary aims will include assessment of the pharmacokinetics of capecitabine and docetaxel on this schedule, and determination of intratumoral Bax:Bcl-2, Bcl-2 phosphorylation, and DPD expression, and correlation with clinical toxicities and antitumor response.