Here is the corresponding Spring XML configuration :
Documentation : http://cxf.apache.org/docs/client-http-transport-including-ssl-support.html
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:http-conf="http://cxf.apache.org/transports/http/configuration"
xmlns:sec="http://cxf.apache.org/configuration/security"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://cxf.apache.org/transports/http/configuration http://cxf.apache.org/schemas/configuration/http-conf.xsd
http://cxf.apache.org/configuration/security http://cxf.apache.org/schemas/configuration/security.xsd">
<http-conf:conduit name="*.http-conduit">
<http-conf:client ProxyServer="proxy" ProxyServerPort="8080"/>
<http-conf:proxyAuthorization>
<sec:UserName>proxy_user</sec:UserName>
<sec:Password>proxy_pass</sec:Password>
</http-conf:proxyAuthorization>
</http-conf:conduit>
In order for this to work you should import cxf.xml :
<import resource="classpath:META-INF/cxf/cxf.xml"/>
Note that this httpConduit will be enabled for all your CXF clients (if several).
You should configure your conduit name to match only your service Conduit :
name="{http://example.com/}HelloWorldServicePort.http-conduit"