Register GoogleCloudMessaging # returns different IDs in the same app / device?

I am using GoogleCloudMessaging to implement notification functionality in my application. But I have a problem: when I uninstall my application and install it again , I got 2 different registration IDs , resulting in duplicate notifications in my strong> application .

In the doc they said, "Repeated calls to this method will return the original registration ID"

public String register (String ... senderIds)

Register your app for GCM and return the registration ID. You have to call this once your app is installed and send the returned registration ID to the server.

Repeated calls to this method return the original registration ID.

But in another document, they came up with something called "Canonical IDs":

Canonical IDs On the server side, as long as the application behaves well, everything should work fine. However, if a bug in the app triggers multiple registrations for the same device, it can be tricky and you might get duplicate messages.

So how can I make this consistent across all devices? My (third party) server stores registration IDs that will be used to send notifications. Now the "Canonical Identifiers" came in and things got so complicated!

Does this mean that I have to send a unique ID for each device when I register?

This is the block of code I used to register the device with GoogleCloudMessaging:

try {
    if (gcm == null) {
        gcm = GoogleCloudMessaging.getInstance(context);
    }
    regid = gcm.register(SENDER_ID);
    Log.d(TAG, "########################################");
    Log.d(TAG, "Current Device Registration ID is: " + regid);
    Map<String, String> data = new HashMap<String, String>();
    data.put("regId", regid);
    try {
        Utils.post(Constants.SERVER_NOTIFY_REG_LINK, data);
        Log.d(TAG, "ID registered: " + regid);
    } catch (Exception e) {
        e.printStackTrace();
    }
} catch (IOException ex) {
    msg = "Error :" + ex.getMessage();
    Log.d(TAG, msg);
}