 Arm 2: Treatment with Paroxetine will be flexible-dose and will be initiated at 10-mg po qhs. For subjects who experienced morning sedation, the dose will be decreased to 5-mg po qhs on day 3. For the subjects who did not achieve a remission of panic symptoms, the dose will be increased to 20-mg po qhs. For the subjects who did not achieve a remission of panic symptoms, the dose will be increased to 40-mg po qhs as needed. 