My object graph has a TopLevel object with an ArrayList of child objects
attached to it. Those child objects may sometimes exist, and sometimes won't
exist. If I don't set anything for the child objects (leave it null), I'm able
to send it to the server side and save it just fine to the datastore. When my
code returns me an instance of what I've just saved, it has trouble reading it
back in. Does the generated actionscript code take into account optional list
parameters?

It keeps dying in the readExternal() method with this error and exception.

faultCode:Server.Acknowledge.Failed faultString:'Didn't receive an acknowledge
message' faultDetail:'Was expecting mx.messaging.messages.AcknowledgeMessage,
but received null'

ArgumentError: Error #2173: Unable to read object in stream. The class
org.granite.messaging.persistence.ExternalizablePersistentList does not
implement flash.utils.IExternalizable but is aliased to an externalizable class.
at ObjectInput/readObject()
at
com.sli.nitroswc.store.data::SWCBase/readExternal()[C:\Development\fb4beta\TestP\
roject1\src\com\sli\nitroswc\store\data\SWCBase.as:161]
at ObjectInput/readObject()
at
mx.collections::ArrayList/readExternal()[E:\dev\beta1\frameworks\projects\framew\
ork\src\mx\collections\ArrayList.as:547]
at
mx.collections::ArrayCollection/readExternal()[E:\dev\beta1\frameworks\projects\\
framework\src\mx\collections\ArrayCollection.as:147]
at ObjectInput/readObject()
at
mx.collections::ArrayList/readExternal()[E:\dev\beta1\frameworks\projects\framew\
ork\src\mx\collections\ArrayList.as:547]
at
mx.collections::ArrayCollection/readExternal()[E:\dev\beta1\frameworks\projects\\
framework\src\mx\collections\ArrayCollection.as:147]