Underage Gambling

I was just reading a news story from a few days ago which was about underage teenagers playing poker online and the story left off with what could be done to prevent this from happening. Traditionally a credit card has been used to verify that the holder is of age. Now I don't know when the last time you were on a college campus or in a high school, but getting a credit card from a bank is really very easy.
The article made the problem seem cut and dried, that anyone under 21 was gambling illegally, well unfortunately it isn't that simple. What makes this problem complicated is that different localities and countries have different ages that someone can gamble at. In Canada it is generally 18 and in the US it's generally 21.

To outline this problem let's say the online casino is based in Canada and the player is 18 but lives in a state were you have to be 21 to gamble. Is this player breaking the law? Are they gambling in Canada or in their home state? What if the casino is located in a country that has no age limit for gambling? What then?

Now I am not saying that online casino shouldn't care about "underage" gamblers, they care a lot about the problem and are trying to stop it from happening but how do you do it and what age do you pick? Unfortunately there is no simple answer to this problem.
If you base it on the players location they lie about their country of origin, credit cards already don't work, monitoring conversations to identify young players won't work, as if you don't chat you can get caught.

Try as the online casino will they are fighting an uphill battle, hopefully those in power will realize that the solution truly lies with parents, I know this is a very unpopular answer right now but I think this is truly the only real answer to this problem.

That's all, I fold.