Inclusion Criteria:

* Biopsy-confirmed malignant melanoma

* Stage IV disease
* Cutaneous or mucosal origin
* Melanoma of unknown primary allowed
* No ocular melanoma
* Measurable or non-measurable disease
* No prior or concurrent brain metastases as confirmed by CT scan or MRI
* Zubrod performance status 0-1
* ANC ≥ 1,500/mm\^3
* Platelet count ≥ 100,000/mm\^3
* Hemoglobin ≥ 9 g/dL
* Serum bilirubin ≤ 1.5 times upper limit of normal (ULN) (including patients with hepatic metastases)
* SGOT or SGPT ≤ 2.5 times ULN (≤ 5 times ULN in the presence of hepatic metastases)
* Serum creatinine ≤ 1.5 times ULN
* Not pregnant or nursing
* Fertile patients must use effective contraception
* No other prior malignancy except for adequately treated basal cell or squamous cell skin cancer, in situ cervical cancer, adequately treated stage I or II cancer from which the patient is currently in complete remission, or any other cancer from which the patient has been disease-free for 5 years
* No prior therapy with a cyclin-dependent kinase inhibitor
* At least 14 days since prior radiotherapy
* At least 28 days since prior systemic chemotherapy
* At least 28 days since prior adjuvant systemic therapy
* At least 28 days since prior surgery
* No more than 1 prior systemic therapy regimen (chemotherapy, biologic/immunotherapy, hormonal therapy, or a combination regimen) for stage IV melanoma and any side effects must have resolved to ≤ grade 1
* Any number of prior adjuvant systemic therapy regimens allowed, including interferon alfa-2b, GM-CSF, chemotherapy, and chemobiotherapy

* Therapy for stage IV resected free-of-disease will be considered adjuvant therapy
* Prior radiotherapy allowed provided any side effects have resolved to ≤ grade 1
* Prior surgery (for both the primary and stage IV disease) allowed provided side effects have resolved to ≤ grade 1
* No other concurrent or planned non-study treatment (including chemotherapy, hormonal therapy, biologic therapy, or radiotherapy)
* No concurrent CYP3A4 inhibitors or inducers
* No concurrent grapefruit or grapefruit juice