JEN ANISTON is officially engaged to her beau JUSTIN THEROUX.

The couple became engaged on his 41st birthday.

Jen is 43.

"Justin Theroux had an amazing birthday on Friday, receiving an extraordinary gift when his girlfriend, Jennifer Aniston, accepted his proposal of marriage," his rep told media.

The couple has been dating since early last 2011, although Jennifer's said they've known each other "for years."

This will be Aniston’s second marriage. She and Brad Pitt divorced in 2005.

Pitt and his partner in parenting Angelina Jolie, are also now engaged and rumored to be getting married soon,

The PR fueled Jen- Angie feud continues unabated,