Azure – Cannot find the X.509 certificate using the following search criteria

I'm trying to set up a WCF service hosted in a Windows Azure Web Role. I've configured the service for message security, so while using an unsecured channel, I want to encrypt the messages using a X509 certificate. Unfortunately, I can't get it to work on Azure. Locally I managed to set everything up correctly.

Here's the web.config of the WCF service:

<behaviors>
  <serviceBehaviors>
    <behavior>
      <!-- To avoid disclosing metadata information, set the value below to false before deployment -->
      <serviceMetadata httpGetEnabled="true" httpsGetEnabled="false"/>
      <!-- To receive exception details in faults for debugging purposes, set the value below to true.  Set to false before deployment to avoid disclosing exception information -->
      <serviceDebug includeExceptionDetailInFaults="true"/>
      <serviceCredentials>
        <serviceCertificate findValue="CN=peterpan.cloudapp.net" storeLocation="LocalMachine" storeName="My" x509FindType="FindBySubjectName" />
        <userNameAuthentication userNamePasswordValidationMode="Custom" customUserNamePasswordValidatorType="Skillconomy.Cloud.CheckInService.UserValidator, Skillconomy.Cloud.CheckInService" />
      </serviceCredentials>
    </behavior>
  </serviceBehaviors>
</behaviors>

I've configured the certificate in the Web Role:

And I've uploaded the certificate in the Azure portal:

I get the exception:

Cannot find the X.509 certificate using the following search
criteria: StoreName 'My', StoreLocation 'LocalMachine', FindType
'FindBySubjectName', FindValue 'CN=xyz.cloudapp.net'. Description: An
unhandled exception occurred during the execution of the current web
request. Please review the stack trace for more information about the
error and where it originated in the code.

Exception Details: System.InvalidOperationException: Cannot find the
X.509 certificate using the following search criteria: StoreName 'My',
StoreLocation 'LocalMachine', FindType 'FindBySubjectName', FindValue
'CN=xyz.cloudapp.net'.

What am I missing here?