A Placebo-controlled Study of Levetiracetam In Children (1mo to 4yrs of Age) With Partial Onset Seizures.

To evaluate the safety and efficacy of levetiracetam used as adjunctive treatment in pediatric subjects age 1 month to less than 4 years with partial onset seizures. Subjects will be evaluated with 48 hour inpatient video electroencephalograms (a selection and an evaluation). Other neuropsychological clinical assessments will be performed during the 34 day length of the study.