Connection to untrusted SSL server fails

[Christopher Horn]

Summary:
When using an SSL-enabled Exchange server, and the certificate is not signed by a trusted CA, the provider fails to connect.

What happens:
No error message is displayed, the calendar just doesn't sync.

What is expected:
An error message indicating that the connection fails because of an untrusted certificate.

Workaround:
Adding the certificate manually to Thunderbird ("Confirm security exception") resolves the issue.

Debug output (when certificate is not added):

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: setup req to https://AD\user@exchange/EWS/Exchange.asmx user AD\user

getInterfaces called

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: Sending: <?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="Exchange2007_SP1"/>
  </soap:Header>
  <soap:Body>
    <m:FindItem Traversal="Shallow">
      <m:ItemShape>
        <t:BaseShape>IdOnly</t:BaseShape>
        <t:AdditionalProperties>
          <t:FieldURI FieldURI="calendar:UID"/>
          <t:FieldURI FieldURI="calendar:CalendarItemType"/>
        </t:AdditionalProperties>
      </m:ItemShape>
      <m:CalendarView StartDate="2012-02-21T13:26:19+01:00" EndDate="2012-03-23T13:26:19+01:00"/>
      <m:ParentFolderIds>
        <t:DistinguishedFolderId Id="calendar"/>
      </m:ParentFolderIds>
    </m:FindItem>
  </soap:Body>
</soap:Envelope>

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: getInterface

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: getInterface

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: IID: {09b54ec1-d98a-49a9-bc95-3219e8b55089}

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: reply

ba180542-4fb2-44dc-93ed-3cd06b6216e9/exchange: connection failure