Passing simple Parameter from one page to another

[coolex]

Hello!

This is a simple question but I couldn't find the answer on the internet or this forum.
I just want to pass a parameter (a task instance) from one page to another.
On the source page I've inserted this button:

<s:button action="#{orderingProcess.endTask()}" taskInstance="#{task}" value="End Task" rendered="#{not empty task.start}">
 <ui:param name="task" value="#{task}"/>
</s:button>

But how can I use this parameter on my destination page? After executing the action (in the button) I will be referenced to another page (with the help of navigation rules). Here I need to use this special task parameter.
I tried something like this:

<h:outputText value="#{param.task.name}"/>

but I wasn't succesfull.

Hope you can help me.
Thanks.
Alex