Lulu's AA bug + video

If Lulu used to shield allies, shield (Lulu's passive) cancels her Auto attack

1. Pick Lulu and a champion with high attack speed , Vayne for example.
2. Use Lulu's shield allies, which uses auto attack.
3. Try using Lulu's AA, while champ is attacking with shield.
4. Notice how each AA is interrupted. Maybe video can show more: https://www.youtube.com/watch?v=IR6edZG6V6I&feature=youtu.be

Do not need have a high attack speed, just when he uses AA at the same time as you, for example on the line, that's a problem. I noticed that this problem persists approximately 4 last patches. I know this because http://www.lolking.net/summoner/eune/35047713

Please fix, because I know that previously worked. Sorry for the bad English, I hope you understand I appreciate any response (◕‿◕✿)