While MultiTap is one of the most popular text entry methods for mobile phones, it has a fundamental weakness known as MultiTap segmentation problem. Based on the observation that the thumb does not leave the keys between tapping actions, we designed a MultiTap segmentation method where the release action of the thumb is used to indicate input completion. A user study using a touch-sensing keypad prototype to explore the feasibility of the idea and a comparison test to access its benefit revealed promising results supporting the effectiveness of the proposed segmentation method.