Weblogic Web service method not associated with a namespace

I am upgrading an EJB Webservice running in Weblogic 8.1 environment to Weblogic 10.3. As per weblogic documentation, i converted the EJB bean class to a normal Java class and added annotation to the Java class to identify it as a Webservice. After building the ear and deploying to a server, i could see my webservice up and running. However, when i trigger a request, which used to give me a valid response in 8.1, to the new 10.3 webservice, i get 'Failed to get Operation Name' error. My input request is like this.

<soapenv:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSc开发者_开发问答hema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:tns="http://mycomputer.com:7101/WebServices/HelloService">
   <soapenv:Header/>
   <soapenv:Body>
      <MyRequest soapenv:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
         <string xsi:type="xsd:string">Hello</string>
      </MyRequest>
   </soapenv:Body>
</soapenv:Envelope>

As you can see, the MyRequest element is not part of any namespace declaration. The 8.1 webservice identifies it to belong to namespace - http://mycomputer.com:7101/WebServices/HelloService. However, the 10.3 webservice doesn't identify the same. When i prefix "tns:" for MyRequest element, i get a valid response from 10.3 webservice. So, my question is

1. Do i have to make any configuration change in 10.3 webservice to handle the 8.1 request as is.
2. Does Weblogic 10.3 enforce each request element belong to a namespace.

Thanks for looking!