mule 3.4.0 spring security with OpenAM

问题

How do I secure a http endpoint in mule using Spring Security with OpenAM as Authentication Provider? I used

<http:inbound-endpoint host="somehost" port="someport" path="myHttp" exchange-pattern="request-response">
 <mule-ss:http-security-filter realm="mule-realm"/>
</http:inbound-endpoint>

but the issue I face is that Mule uses DefaultMuleAuthentication whose getCredentials() returns a String while OpenAM is looking for com.iplanet.sso.SSOToken and I get java.lang.String cannot be cast to com.iplanet.sso.SSOToken.

来源：https://stackoverflow.com/questions/19141638/mule-3-4-0-spring-security-with-openam