otpadmin redirects to otp

I’m trying to use the OTP Login Module. Strangely whenever I’m calling the admin web-module with the URL http://java-as:port/otpadmin it redirects to the otp user interface (http://java-as:port /webdynpro/resources/sap.com/sso~otp~wd/OTP#). Tracing didn’t give me any further clue. Why is this happening? Any idea is highly appreciated.