DISEASE CHARACTERISTICS:

* Histologically or cytologically confirmed adenoid cystic, lymphoepithelioma-like, or myoepithelial salivary gland cancer

* Unresectable AND/OR
* Radiologically documented metastatic disease
* c-kit positive tumor (1+, 2+, or 3+)
* At least 1 unidimensionally measurable lesion

* More than 20 mm by conventional techniques OR
* More than 10 mm by spiral CT scan
* No known brain metastases

PATIENT CHARACTERISTICS:

Age

* 18 and over

Performance status

* ECOG 0-2

Life expectancy

* More than 12 weeks

Hematopoietic

* Absolute neutrophil count greater than 1,500/mm3
* Platelet count greater than 100,000/mm3

Hepatic

* Bilirubin less than 1.25 times upper limit of normal (ULN)
* AST/ALT less than 2.5 times ULN

Renal

* Creatinine less than 1.25 times ULN OR
* Creatinine clearance greater than 50 mL/min

Cardiovascular

* No myocardial infarction within the past 6 months
* No congestive heart failure
* No unstable angina
* No active cardiomyopathy
* No unstable ventricular arrhythmias
* No uncontrolled hypertension

Other

* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective barrier contraception during and for 3 months after study
* No other active malignancy within the past 5 years except adequately treated carcinoma in situ of the cervix or non-melanomatous skin cancer
* No uncontrolled psychotic disorders
* No serious infections
* No active peptic ulcer disease
* No other serious medical condition that would preclude study
* No prior allergy to compounds of similar chemical or biologic composition as imatinib mesylate

PRIOR CONCURRENT THERAPY:

Biologic therapy

* No concurrent filgrastim (G-CSF)

Chemotherapy

* At least 4 weeks since prior chemotherapy and recovered
* No concurrent chemotherapy

Endocrine therapy

* Not specified

Radiotherapy

* At least 4 weeks since prior radiotherapy and recovered
* No concurrent radiotherapy to sites of measurable disease

Surgery

* At least 4 weeks since prior surgery and recovered

Other

* No other concurrent investigational agents
* No concurrent therapeutic warfarin

* Mini-dose warfarin for prophylaxis or low-molecular weight heparin allowed
* No concurrent erythromycin
* No concurrent acetaminophen doses exceeding 3 g/day