Generated requests & responses miss namespace prefix

I'm sorry, it was my fault, SoapUI works correctly. The XSD didn't contain the attribute @elementFormDefault, that's why the generated request & response elements didn't contain the namespace prefix. After adding this attribute:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<xs:schema version="1.0" targetNamespace="http://www.example.com/" elementFormDefault="qualified" 
 xmlns:tns="http://www.example.com/" 
 xmlns:xs="http://www.w3.org/2001/XMLSchema">

  <xs:element name="getGreeting" type="tns:TgetGreeting"/>

  <xs:element name="getGreetingResponse" type="tns:TgetGreetingResponse"/>

  <xs:complexType name="TgetGreeting">
    <xs:sequence>
      <xs:element name="name" type="xs:string" minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>

  <xs:complexType name="TgetGreetingResponse">
    <xs:sequence>
      <xs:element name="return" type="xs:string" minOccurs="0"/>
    </xs:sequence>
  </xs:complexType>
</xs:schema>

SoapUI generates correct requests with namespace prefixes.