DISEASE CHARACTERISTICS:

• Diagnosis of one of the following:

  • Confirmed chronic lymphocytic leukemia (CLL), meeting the following criteria:

    • Peripheral blood lymphocytosis greater than 5,000/mm^3
    • Co-expression of the CD5, CD19, CD20, and CD23 surface antigens
    • Clonal kappa and lambda light chain expression
    • Dim surface immunoglobulin expression
  • Small lymphocytic lymphoma

• Relapsed or refractory disease

  • Must have received at least 1 prior regimen containing fludarabine

  • Meets one of the following criteria:

    • Recurrence of lymphocytosis greater than 5,000/mm^3 or an increase in lymph node volume greater than 50% after achieving complete (CR) or partial response (PR)
    • Never achieved a CR or PR after receiving at least 2 courses of fludarabine IV for 5 days at a dose of 25 mg/m^2/day
• No other lymphoproliferative diseases or diseases due to transformation of CLL (e.g., prolymphocytic leukemia or Richter's syndrome)
• No known CNS disease

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• Karnofsky 60-100%

Life expectancy:

• At least 12 weeks

Hematopoietic:

• See Disease Characteristics

Hepatic:

• Bilirubin < 2.0 times upper limit of normal (ULN)*
• SGOT < 2.5 times ULN* NOTE: *Unless due to Gilbert's disease OR the result of CLL

Renal:

• Creatinine < 1.5 times ULN

Cardiovascular:

• No history of cardiac arrhythmia
• No myocardial infarction within the past 6 months

Other:

• No other malignancy within the past 5 years except basal cell skin cancer or carcinoma in situ of the cervix
• No active serious infection uncontrolled by antibiotics
• No pre-existing neurotoxicity grade 3 or greater
• No other medical condition that would preclude study participation
• Not pregnant or nursing
• Negative pregnancy test
• Female patients must use 2 effective methods (at least 1 highly active method) of contraception 4 weeks before, during, and for 4 weeks after study participation and male patients must use effective barrier contraception during and for 4 weeks after study participation

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 4 weeks since prior biologic therapy and recovered
• No concurrent growth factors (epoetin alfa, filgrastim [G-CSF], or sargramostim [GM-CSF])

Chemotherapy:

• See Disease Characteristics
• No more than 3 prior chemotherapy regimens
• At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas) and recovered
• No other concurrent chemotherapy

Endocrine therapy:

• Not specified

Radiotherapy:

• At least 4 weeks since prior radiotherapy and recovered
• No concurrent radiotherapy

Surgery:

• Not specified

Other:

• Recovered from any prior investigational agents
• No other concurrent investigational agents