Exchange Web Services - cannot get additional properties when calling "FindPeople" method - web-services

Question

I'm making raw SOAP requests to Office365 and trying to get a list of contacts for specified AddressListId I successfully get a list of contacts, but it does not include all additional information I need. Once I add some additional properties (e.g. PhoneNumber) to my request, the server returns Invalid shape error.
Here is my request:
<?xml version="1.0" encoding="UTF-8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/"
xmlns:t="http://schemas.microsoft.com/exchange/services/2006/types"
xmlns:m="http://schemas.microsoft.com/exchange/services/2006/messages">
<soap:Header>
<t:RequestServerVersion Version="Exchange2013" />
</soap:Header>
<soap:Body >
<m:FindPeople>
<m:PersonaShape>
<t:BaseShape>IdOnly</t:BaseShape>
<t:AdditionalProperties>
<t:FieldURI FieldURI="persona:DisplayName"/>
<t:FieldURI FieldURI="persona:PhoneNumber"/>
</t:AdditionalProperties>
</m:PersonaShape>
<m:IndexedPageItemView BasePoint="Beginning" MaxEntriesReturned="100" Offset="0"/>
<m:ParentFolderId>
<t:AddressListId Id="###-####-####-####"/>
</m:ParentFolderId>
</m:FindPeople>
</soap:Body>
</soap:Envelope>
How can I get all additional information for each persona?

Answer 1

I am using EWS Managed API, so you will have to search for the raw SOAP calls on MSDN, I can only direct your search a bit:
I had a similar problem, because the very same is applicable for FindAppointments(). Asking for AppointmentSchema.RequiredAttendees will raise the Invalid Shape error, and AppointmentSchema.Organizer won't contain the email address, only the name of the organizer, after using FindAppointments().
The solution was to do TWO requests to Exchange Server.
var appointments = calendarFolder.FindAppointments(BasePropertySet.FirstClassProperties);
exchangeService.LoadPropertiesForItems(appointments, MyAdvancedProperties);
I think that the same "workaround" is possible with FindPeople(), as well as every other Find%Itemtype%() EWS may support, I am not sure, though.
EDIT: I just found http://social.technet.microsoft.com/Forums/exchange/en-US/e83abfb1-37a8-48fe-9579-4e120fb77746/ews-managed-api-loadpropertiesforitems-returns-unexpected-end-of-xml-document?forum=exchangesvrdevelopment where it is stated that LoadPropertiesForItems does a call to raw soap GetItem with multiple ItemIDs.