Inclusion Criteria:

- Patients with the following disease: Idiopathic myelofibrosis, or spent PV-, or
ET-related myelofibrosis in chronic phase (<20% blast cells in the bone marrow) with
Lille score >1 at any time, or platelet <100K.

- Age 18-65 years.

- ECOG performance status < 3.

- Life expectancy >3 months.

- Adequate cardiac function, normal LVEF ≥ 45% by MUGA or echocardiogram and adequate
pulmonary function DLCO ≥ 50% of predicted.

- Serum creatinine < 1.1 x the upper limit of normal (ULN) or Creatinine Clearance >50
ml/min.

- Serum bilirubin < 2.0 mg/dl, SGPT <2.5 x upper limit of normal

- No evidence of chronic active hepatitis or cirrhosis

- HIV-negative

- Patient is not pregnant

- Patient or guardian able to sign informed consent.

- Patients with >20% myeloblasts in the blood or marrow, extramedullary blast cell
proliferation or large foci of blasts in bone marrow biopsy specimens are not
eligible.

- Pretransplant splenectomy: MMM patients with variable degrees of splenomegaly, or
splenectomized, are eligible to be enrolled. Any decision of having a patient
splenectomized prior to transplant will be made in each center prior to enrolling the
patient in the study.

- Patients should be off treatment with investigational for at least 4 weeks and have
recovered from all toxicities.

Exclusion Criteria:

- Pregnancy

- HIV positive

- > 20% myeloblasts in the peripheral blood or bone marrow

- LVEF < 45%

- DLCO < 50% of predicted

- ECOG performance status ≥ 3

- Chronic active hepatitis or cirrhosis

- Chronic renal insufficiency