Properties placeholders on camel-cxf configuration in Blueprint

Issue

I am using property placeholder for a camel route that involves camel-cxf endpoint in blueprint. Some of the CXF bean configuration elements seem not to resolve the property placeholders:

<cm:property-placeholder id="myPlaceHolder" persistent-id="cmProp" placeholder-prefix="{{" placeholder-suffix="}}">
      <cm:default-properties>
          <cm:property name="propDir" value="/Users/jluo/config" ></cm:property>
          <cm:property name="propFile" value="wss4jConfig.properties" ></cm:property>
      </cm:default-properties>
  </cm:property-placeholder>

  <ext:property-placeholder id="ext-placeholder">
      <ext:default-properties>
      </ext:default-properties>
      <ext:location>file:{{propDir}}/{{propFile}}</ext:location>
  </ext:property-placeholder>

  <camelcxf:cxfEndpoint id="reportIncident"
                    address="{{connector.input.http.cxf}}"
                    wsdlURL="META-INF/wsdl/report_incident.wsdl"
                    serviceClass="org.apache.camel.example.reportincident.ReportIncidentEndpoint"
                    endpointName="s:ReportIncidentService"
                    serviceName="s:ReportIncidentEndpointService"
                    xmlns:s="http://reportincident.example.camel.apache.org">
      <camelcxf:inInterceptors>
          <bean class="org.apache.cxf.interceptor.LoggingInInterceptor"></bean>
          <bean class="org.apache.cxf.ws.security.wss4j.WSS4JInInterceptor">
              <property name="properties">
                  <map>
                      <entry key="action" value="Signature"></entry>
                      <entry key="user" value="clientx509v1"></entry>
                      <entry key="passwordCallbackClass" value="org.apache.camel.example.reportincident.ServerUTPasswordCallback"></entry>
                      <entry key="signaturePropRefId" value="inSignatureProperties"></entry>
                      <entry key="inSignatureProperties" value-ref="inCryptoProperties"></entry>
                      <entry key="signatureKeyIdentifier" value="DirectReference"></entry>
                  </map>
              </property>
          </bean>
          <bean class="org.apache.cxf.ws.security.wss4j.DefaultCryptoCoverageChecker">
              <property name="signBody">
                  <value type="java.lang.Boolean">true</value>
              </property>
          </bean>
      </camelcxf:inInterceptors>
      <camelcxf:outInterceptors>          
        <bean class="org.apache.cxf.interceptor.LoggingOutInterceptor"></bean>
          <bean class="org.apache.cxf.ws.security.wss4j.WSS4JOutInterceptor">
              <property name="properties">
                  <map>
                      <entry key="action" value="Signature"></entry>
                      <entry key="user" value="serverx509v1"></entry>
                      <entry key="passwordCallbackClass" value="org.apache.camel.example.reportincident.ServerUTPasswordCallback"></entry>
                      <entry key="signaturePropRefId" value="outSignatureProperties"></entry>
                      <entry key="outSignatureProperties" value-ref="outCryptoProperties"></entry>>
                      <entry key="signatureKeyIdentifier" value="DirectReference"></entry>
                      <entry key="signatureParts" value="{Element}{http://schemas.xmlsoap.org/soap/envelope/}Body"></entry>
                  </map>
              </property>
          </bean>
    </camelcxf:outInterceptors>
    <camelcxf:properties>
    <entry key="dataFormat" value="CXF_MESSAGE"></entry>
    </camelcxf:properties>
  </camelcxf:cxfEndpoint>

    <bean id="inCryptoProperties" class="java.util.Properties">
      <argument>
        <props>
          <prop key="org.apache.ws.security.crypto.provider">org.apache.ws.security.components.crypto.Merlin</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.type">jsk</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.password">storepassword</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.alias">clientx509v1</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.file">{{connector.input.http.cxf.keystore}}</prop>
        </props>
      </argument>
    </bean>

    <bean id="outCryptoProperties" class="java.util.Properties">
      <argument>
        <props>
          <prop key="org.apache.ws.security.crypto.provider">org.apache.ws.security.components.crypto.Merlin</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.type">jks</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.password">storepassword</prop>
          <prop key="org.apache.ws.security.crypto.merlin.keystore.alias">serverx509v1</prop> 
          <prop key="org.apache.ws.security.crypto.merlin.keystore.file">{{connector.output.http.cxf.keystore}}</prop> 
        </props>
      </argument>
    </bean>

  <bean id="reporaIncidentProcessor" class="org.apache.camel.example.reportincident.ReportIncidentProcessor"></bean>

  <camelContext id="camel" xmlns="http://camel.apache.org/schema/blueprint">
    <route>
        <from uri="cxf:bean:reportIncident"></from>
        <process ref="reporaIncidentProcessor"></process>
    </route>
    <route>
        <from uri="timer://foo?repeatCount=1"></from>
        <log message="The property value of connection.input.http.cxf: {{connector.input.http.cxf}}"></log>
    </route>
  </camelContext>

</blueprint>

The property placeholder

address="{{connector.input.http.cxf}}"

works fine for camel-cxf endpoint while the property placeholders defined in the Properties beans:

<prop key="org.apache.ws.security.crypto.merlin.keystore.file">{{connector.input.http.cxf.keystore}}</prop>

and

<prop key="org.apache.ws.security.crypto.merlin.keystore.file">{{connector.output.http.cxf.keystore}}</prop>

do not work.

Any idea why?