1. Mild to moderate hypertension as defined by a morning mean(>95 and <115mmHg) of two diastolic blood pressure measurements (DBP) after 5 min in the sitting position following a minimum 2-week placebo run in phase.Mean sitting systolic blood pressure (SBP) must be >140 and <200mmHg. The mean DBP and SBP values are calculated as the mean of the two sitting measurements taken 2 min apart just before the drug intake.