how to encrypt values in a properties file in spring for .net v1.3

I am using .net 4.0 with spring.net v1.3 for IoC. My property placeholder is in a properties file (i.e. app.properties), where each line is a key-value pair (i.e. smtp.port=25). i would like for some of these values (username/password) to be encrypted in the properties file, and then have spring automagically decrypt the values when it instantiates/injects the objects. Is this p开发者_如何学编程ossible out-of-the-box using Spring.Net v1.3?

Implement you own IVariableSource : http://www.springframework.net/doc-latest/reference/html/objects.html#objects-variablesource