Double tagging vlan attack agains Procurve Switches

Hello chaps!!

I am currently investigating the double tagging attack in order to prevent my network of possible security flaws.

The attack concept seems quite straightforward. But I am unable to launch the attack successfully so I began to think that Procurve Switches have a kind of inbuilt security for this kind of attack.

I have been testing the attack using Yersinia and 2 lab Procurve switches with the default configuration plus the required vlan configuration to simulate the attack.

Any thoughts on the matter? Has anyone here performed a successfully attack against Procurve switches using this technique?

Thanks for your help.