Plugins, Messages, and StateCode access

This is in a 2011 CRM Online instance.

We currently have post-operation plugins registered on the QueueItem Entity for the SetState and SetStateDynamicEntity messages. When the related Entity's state, in this case an opportunity, forces the QueueItem to an Inactive state the plugins are not firing. We have removed all code and thrown exceptions immediately in the plugins just to confirm that it is in fact completely skipping the firing of these messages in this use case.

The Update Plugin I registered Post-Operation is firing however. To verify, I've filtered this plugin down to just the StateCode in the filtering Attribute. It still fires on the QueueItem when you close the related opportunity with a Won/Lost.s

The problem is that it will not allow me to access the StateCode from the Context or the Post Image Alias. I get  the following exception when I pull the StateCode:

Entity QItem = (Entity)context.InputParameters["Target"];

localContext.TracingService.Trace("Retrieving postState");
                            int postState = ((OptionSetValue)QItem.Attributes["StateCode"]).Value;

<OrganizationServiceFault xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.microsoft.com/xrm/2011/Contracts"><ErrorCode>-2147220956</ErrorCode><ErrorDetails xmlns:d2p1="http://schemas.datacontract.org/2004/07/System.Collections.Generic" /><Message>Unexpected exception from plug-in (Execute): GracoCustomizations.Plugins.PostQueueItemUpdate: System.Exception: Error in PostQueueItemUpdate Plug-in:The given key was not present in the dictionary.</Message><Timestamp>2013-06-28T21:00:14.3469294Z</Timestamp><InnerFault i:nil="true" /><TraceText>

[GracoCustomizations.Plugins: GracoCustomizations.Plugins.PostQueueItemUpdate]
[7319d0df-8db7-e211-8a81-78e3b508f865: PostQueueItemUpdate]

Entered GracoCustomizations.Plugins.PostQueueItemUpdate.Execute(), Correlation Id: f6dd58f7-81ed-4313-bef5-eec72574f2d1, Initiating User: cfad9426-55a1-45a3-8f5f-558da43a8d07
GracoCustomizations.Plugins.PostQueueItemUpdate is firing for Entity: queueitem, Message: Update, Correlation Id: f6dd58f7-81ed-4313-bef5-eec72574f2d1, Initiating User: cfad9426-55a1-45a3-8f5f-558da43a8d07
Recieved QueueItem Context. 
Recieved Org Service. 
Should be an Oppt: 3
Preparing to Assign Pre UserIDs: a81d9444-2ae0-e211-8985-78e3b508f865
Preparing to Assign Post UserIDs. a81d9444-2ae0-e211-8985-78e3b508f865
Retrieving postState
Exiting GracoCustomizations.Plugins.PostQueueItemUpdate.Execute(), Correlation Id: f6dd58f7-81ed-4313-bef5-eec72574f2d1, Initiating User: cfad9426-55a1-45a3-8f5f-558da43a8d07


</TraceText></OrganizationServiceFault>

Is this expected behavior or did we miss something? We have other plugins registered for state change messages that fire even when the change is initiated from an Opportunity, it seems on the surface that these should fire as well. Also, what is up with the StateCode in an Update that fires specifically on a statecode change? We are fine with handling it either way if someone has a solution to either problem.

Thanks for any guidance on this issue.

Jason