The purpose of this study is to investigate the safety and effectiveness of ciclesonide nasal spray as compared with placebo (inactive substance) nasal spray in relieving symptoms of seasonal allergic rhinitis caused by pollen. Ciclesonide will be administered once during the exposure to ragweed pollen in a controlled environment. The study duration consists of a baseline period (up to 5 days) and a treatment period (1 day). The study will provide further data on safety and tolerability of ciclesonide.