KeyRemap4MacBook private.xml, Alt Gr in Remote Desktop Conn.

<?xml version="1.0"?>
<root>
    <item>
        <name>Option_R to Control_L+Option_L (only in Remote Desktop)</name>
        <identifier>remap.optionR2controlLoptionL</identifier>
        <only>VIRTUALMACHINE, REMOTEDESKTOPCONNECTION</only>
        <autogen>__KeyToKey__ KeyCode::OPTION_R, KeyCode::CONTROL_L, ModifierFlag::OPTION_L</autogen>
    </item>
</root>