Thanks for the example. It helped a lot to find out the problem
To reproduce it properly it is necessary to set this param:
and PSS should be disabled.
There are two small bugs:
1. We don't enable PSS when faces-config version is 2.1, only when 2.0 is set. We need to add that check too.
2. There are some wrappers for ValueExpression/MethodExpression that requires to implement Externalizable, to be saved and restored correctly.
The good news are if you add this on your web.xml:
PSS will be enabled and everything will work well. Thanks a lot for the examples, they were very useful solving this issue.