Camel loadBalance failover maximumFailoverAttempts doesn't support properties

Issue

• On JBoss Fuse 6.2.1 Apache Camel 2.15.1, when I have

<loadBalance inheritErrorHandler="false" id="load-balance">
<failover maximumFailoverAttempts="2">
    <exception>java.net.ConnectException</exception>
    <exception>org.apache.cxf.transport.http.HTTPException</exception>
</failover>
<to id="sender-service1" uri="cxf:bean:some-service1-endpoint" />
<to id="sender-service2" uri="cxf:bean:some-service2-endpoint" />

• It works but when I try and use a parameter for maximumFailoverAttempts

<failover maximumFailoverAttempts="">

• I get the error:

    Caused by: org.xml.sax.SAXParseException: cvc-datatype-valid.1.2.1: '' is not a valid value for 'integer'.

• If I try and use "Using property placeholders for any kind of attribute in the XML DSL" from http://camel.apache.org/using-propertyplaceholder.html as described in Validation error with integer property (camel) e.g.

<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:camel="http://camel.apache.org/schema/spring" xmlns:context="http://www.springframework.org/schema/context"
xmlns:prop="http://camel.apache.org/schema/placeholder"

    <failover prop:maximumFailoverAttempts="">

• I then get the error:

    Caused by: org.xml.sax.SAXParseException: cvc-complex-type.3.2.2: Attribute 'prop:maximumFailoverAttempts' is not allowed to appear in element 'failover'.

• We are using other Camel properties and the property is set in our configuration file. How can I use a parameter for the maximumFailoverAttempts attribute?