MAStringReader and nil

Hi, We'd like some help with how nil / undefined is handled in Magritte, and specifically a MAStringDescription. The method MAStringReader >> read:description: overrides the default behaviour to return nil. Is a nil in Magritte seen as a "unpopulated" token? Our problem more specifically is this: We start with an object containing an string in an instance variable. We use a MAStringDescription for this instance variable. We use the magritte-seaside binding to edit this field on the UI. If the user does not capture text in the text input, an empty string is "written". The method on MAStringReader mentioned above intercepts this and returns nil, so nil is written back to our domain object, where we started off with an empty string. We do not want nils to be written into our domain object where we initialized it with an empty string. How do we fix this? Is there a hook where we should be specifying this? Or is there a fundamental way of working with Magritte-Seaside where it will write nils and we have to manage that on our domain object? Thanks for your help. Otto