RPC ietf-netconf:edit-config removes device namespaces

I used to send the following ietf-netconf:edit-config RPC, back in Boron-SR3, that worked fine:
 
<input xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<target>
<candidate/>
</target>
<default-operation>none</default-operation>
<config>
  <interface-configurations xmlns="http://cisco.com/ns/yang/Cisco-IOS-XR-ifmgr-cfg">
    <interface-configuration>
      <active>pre</active>
      <interface-name>TenGigE0/0/0/0</interface-name>
      <interface-mode-non-physical>default</interface-mode-non-physical>
      <description>test</description>
    </interface-configuration>
  </interface-configurations>
</config>
</input>
 
That same RPC fails in latest ODL (Flurine SR1); from the log, here is the message being sent to the device along with the error message replied.
 
<rpc message-id="m-0" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<edit-config>
<target>
<candidate/>
</target>
<default-operation>none</default-operation>
<config>
  <interface-configurations>
    <interface-configuration>
      <active>pre</active>
      <interface-name>TenGigE0/0/0/0</interface-name>
      <interface-mode-non-physical>default</interface-mode-non-physical>
      <description>test</description>
    </interface-configuration>
  </interface-configurations>
</config>
</edit-config>
</rpc>
, response: <rpc-reply xmlns="urn:ietf:params:xml:ns:netconf:base:1.0" message-id="m-0">
 <rpc-error>
  <error-type>protocol</error-type>
  <error-tag>unknown-namespace</error-tag>
  <error-severity>error</error-severity>
  <error-info>
   <bad-element>interface-configurations</bad-element>
   <bad-namespace>urn:ietf:params:xml:ns:netconf:base:1.0</bad-namespace>
  </error-info>
 </rpc-error>
</rpc-reply>
 
As you can see, the namespace has been stripped out, hence device is unable to recognize the element I’m trying to configure.