Vandetanib and Sirolimus in Patients With Recurrent Glioblastoma

* Vandetanib will be given to participants in tablet form. The dose taken will depend upon when they are enrolled in the study. The doctor will inform them of which dose they are on and how many tablets they will be taking. * Sirolimus will also be given to participants in tablet form. The dose taken will depend upon when they are enrolled in the study. The dose on the first day will be higher than the dose taken every other day. * Participants will also be given Bactrim, one double-strength table three times each week (Monday, Wednesday, Friday) to help prevent participants from getting a type of pneumonia called pneumocystis pneumonia. * The following tests and procedures will be performed before the participants begin taking the study drugs and before every 4 week cycle: Physical exam; medical history; questions about any side effects; tumor assessment by MRI or CT (only before every other cycle); Mini-Mental Status exam (MMSE); ECG (week 1, 2, 4, 8, 12, then every 3 months thereafter); blood pressure; blood tests and urine tests. * Participants will be in this research study for a maximum of 12 months.