Potentially there can be an API breaking when upgrading from Camel 1.3 or older. We are sorry for this and will try to refrain from such API breakings in the future Camel 1.x releases. An API overhaul is scheduled for Camel 2.0.
CamelTemplate has been marked as @deprecated and you should use ProducerTemplate instead.
From Camel 1.4.0 on the ProducerTemplate must be retrieved from the CamelContext. You can then use it the same way as before.
Bean component sets a reference to the bean that is being invoked as a property on the Exchange. This property has change its key from "CamelBean" to "org.apache.camel.bean.BeanHolder" and the type is now a BeanHolder.
Camel deployed as a web application in WebSphere 6.1 can not discover annotated converters.
Important changes to consider when upgrading
In Camel 1.4 the Camel JMX agent has been enabled by default. To disable it, as the default in previous versions, you have to explicitly disable it. See the Camel JMX documentation for details.
In Camel 1.4 the DSL for intercept() has changed its default behavior to proceed by default.
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