Need help for HP Service Manager SOAP API consuming using java (axis)

Hello,

Firstly I'll like to make this clear I'm very new to web-services . So coming to my question  I've been given a wsdl file of Incident management using which I've to retreive all the incidents lists and their data using java code.I tried my code firstly to authenticate and I was authenticated but all of a sudden I'm getting 401 authetication error.Can Someone help me with this?