Inclusion Criteria:

- Life expectancy at least 3 months

- Bilirubin normal

- Creatinine normal OR creatinine clearance ≥ 60 mL/min

- No symptomatic congestive heart failure

- No unstable angina pectoris

- No cardiac arrhythmia

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No ongoing or active infection

- No psychiatric illness or social situation that would preclude study compliance

- No history of allergic reaction attributed to compounds of similar chemical or
biological composition to suberoylanilide hydroxamic acid

- No other uncontrolled illness

- Prior adjuvant interferon for stage II or stage III disease allowed

- Prior vaccine therapy as adjuvant therapy or for metastatic disease allowed

- No more than 1 prior cytokine and/or chemotherapy regimen for metastatic disease

- No concurrent prophylactic hematopoietic colony-stimulating factors except
erythropoietin

- More than 4 weeks since prior chemotherapy (6 weeks for nitrosoureas or mitomycin)
and recovered

- No concurrent steroids except topical or inhaled steroids

- More than 4 weeks since prior radiotherapy and recovered

- At least 2 weeks since prior valproic acid

- No concurrent combination antiretroviral therapy for HIV-positive patients

- No other concurrent investigational agents

- No other concurrent anticancer agents or therapies

- Histologically or cytologically confirmed melanoma (metastatic or unresectable
disease)

- The following melanoma types are allowed:

- Cutaneous

- Mucosal

- Ocular

- Unknown primary

- Evidence of residual, recurrent, or metastatic disease by radiographic examination

- Measurable disease, defined as >= 1 unidimensionally measurable lesion >= 20 mm by
conventional techniques OR >= 10 mm by spiral CT scan (tumor lesions located within a
previously irradiated volume that are the only site of measurable disease must have
clear evidence of progression)

- WBC >= 3,000/mm^3

- Absolute neutrophil count >= 1,500/mm^3

- Platelet count >= 100,000/mm^3

- AST and ALT =< 2.5 times upper limit of normal

- ECOG 0-2 OR Karnofsky 60-100%

- No known brain metastases