Deserializing a boolean value with nullable attribute?

Deserializing a boolean value with nullable attribute?

I am deserializing a string back to an object using C#. The xml string
looks like
"<Authentication xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\">
<Status>Success</Status>
<Available i:nil=\"true\"/>
</Authentication>"
While I'm managed to handle the Available by making the bool property
nullable, I'm just wondering what is the correct way to handle
i:nil=\"true\"?
Should I being doing something else other than just making a property
Available property nullable?
Thanks.