Inclusion Criteria:

1. Subject was previously diagnosed with multiple myeloma based on standard diagnostic
criteria, as follows.

Major criteria:

- Plasmacytomas on tissue biopsy.

- Bone marrow plasmacytosis (> 30% plasma cells).

- Monoclonal immunoglobulin spike on serum electrophoresis immunoglobulin G (IgG)
>3.5 g/dL or immunoglobulin A (IgA) > 2.0 g/dL; kappa or lambda light chain
excretion > 1 g/day on 24 hour urine protein electrophoresis.

Minor criteria:

- Bone marrow plasmacytosis (10 to 30% plasma cells).

- Monoclonal immunoglobulin present but of lesser magnitude than given under major
criteria.

- Lytic bone lesions.

- Normal IgM < 50 mg/dL, IgA < 100 mg/dL or IgG < 600 mg/dL.

2. Any of the following sets of criteria will confirm the diagnosis of multiple myeloma:

3. Any two of the major criteria.

4. Major criterion 1 plus minor criterion b, c, or d.

5. Major criterion 3 plus minor criterion a or c.

6. Minor criteria a, b, and c or a, b, and d.

7. Patients must have relapsed or refractory disease (refractory is defined as
progression during treatment or within 60 days after the completion of treatment).

8. Patients must have been previously treated with bortezomib. Patients may have
received prior perifosine.

9. Age >= 18 years at the time of signing informed consent document.

10. All necessary baseline studies for determining eligibility must be obtained within 14
days prior to enrollment. (Pregnancy test must be within 7 days for women of
childbearing potential.)

11. Subject has an ECOG (Zubrod) performance status of 0 to 2.

12. Subject must be able to adhere to the study visit schedule and other protocol
requirements.

13. Subject must understand and voluntarily sign an informed consent document.

14. Women of child-bearing potential (WCBP)— must have a negative serum or urine
pregnancy test within 72 hours prior to enrollment. In addition, all sexually active
WCBP and male patients must agree to use adequate contraceptive methods (oral,
injectable, or implantable hormonal contraceptive; tubal ligation; intra-uterine
device; barrier contraceptive with spermicide; or vasectomized partner) throughout
the study.

Exclusion Criteria:

1. Renal insufficiency (serum creatinine levels > 3 mg/dL).

2. Patients who present with either ALT or AST >= 2.5 X upper limit of normal (ULN)
and/or patients with bilirubin >= 1.5 X ULN.

3. History of allergic reactions attributed to compounds of similar chemical or biologic
composition to perifosine (miltefosine or edelfosine).

4. Concomitant medications that include corticosteroids (except as indicated for other
medical conditions or up to 100 mgs of hydrocortisone or equivalent as premedication
for administration of certain medications or blood products), chemotherapy, or other
therapy that is or may be active against myeloma within 2 weeks prior to Cycle 1 Day
1. Nitrosoureas must be discontinued 6 weeks prior to Cycle 1 Day 1.

5. Subjects with hemoglobin < 8.0 g/dL.

6. Subjects with an absolute neutrophil count (ANC) <= 500 cells/mm3.

7. Peripheral neuropathy of grade 3 or greater. Patients with painful grade 2
neuropathy are also excluded.

8. Subjects with evidence of mucosal or internal bleeding and/or platelet refractory
(i.e., unable to maintain a platelet count >= 50,000 cells/mm3).

9. Previous history of intolerance of bortezomib or perifosine.

10. Any condition, including laboratory abnormalities, that in the opinion of the
investigator places the subject at unacceptable risk if he/she were to participate in
the study.

11. WCBP who are pregnant or breast-feeding or men and women who are not using adequate
contraception.

12. Plasma cell leukemia at time of study entry.