Samarium Sm 153 Lexidronam Pentasodium Combined With Zoledronic Acid or Pamidronate in Treating Patients With Relapsed or Refractory Multiple Myeloma and Bone Pain

RATIONALE: Radioactive drugs, such as samarium Sm 153 lexidronam pentasodium, may carry radiation directly to cancer cells and not harm normal cells. Zoledronic acid and pamidronate may help relieve bone pain caused by multiple myeloma. Giving samarium Sm 153 lexidronam pentasodium together with zoledronic acid or pamidronate may be an effective treatment for multiple myeloma. PURPOSE: This phase I/II trial is studying the side effects and best dose of samarium Sm 153 lexidronam pentasodium when given together with zoledronic acid or pamidronate and to see how well it works in treating patients with relapsed or refractory multiple myeloma and bone pain.