How to use "Receive files anytime" airdrop feature between two MBP?

Hello,

I'm trying to send files between my two macbook pros (mid-2010 and late 2013) without having Airdrop selected in the finder, as mentioned on Yosemite page, but I only get a "Waiting" message, and nothing is sent. Is my 2010 MBP too old for this feature or am I doing something wrong ? Thanks !
For reference:

"Receive files anytime AirDrop in OS X Yosemite allows you to receive files even when AirDrop is not selected in the Finder. You can choose to make yourself available to those in your contacts or to everyone. When a file is sent to you, it appears as a notification. Click to download the file."