Jenkins has just returned from North America where he was working with the Welsh team as their kicking coach. Wales beat Ca ada and the USA in their two summer Tests.
In 1997, Jenkins switched from outside-half to full back and kicked 41 points in the series, including five penalties in each of the first two Tests to steer the Lions to a 2-1 triumph.
Lions head coach Ian McGeechan didn't include a kicking coach among his back room team to come to South Africa, although Jenkins gave Wales No10 Stephen Jones a tip sheet to take with him to use on tour.
But now it has emerged that Jenkins will be in South Africa for the latter stages of the tour and tour manager Gerald Davies has invited him to join the coaching team.
"We did not appoint a kicking coach initially as Rob Howley and Shaun Edwards have experience in this area and have adequately taken responsibility for looking after the kickers," explained McGeechan.
"However, when someone of Neil's ability is available and on hand it would be foolish not to take advantage of it. If anyone knows about what is required in terms of general kicking and goal kicking in South Africa it is Neil.
"It was his all-round kicking game that helped the Lions to victory in the 1997 Test series out here against the then world champions."
Jenkins held the world points record before Jonny Wilkinson overtook him and played four Tests for the Lions in 1997 and 2001.
"It is a great honour to be part of a British & Irish Lions tour and I am delighted and grateful to have been offered this fantastic opportunity," said Jenkins.
"I am extremely lucky in that I have just completed a great tour of Canada and the USA with Wales so I am now free to devote all my attention to the Lions. I have clear ideas of what I would like to contribute and I know so many of the players, coaches and back up team that I will be able to get out onto the training pitch and get started as soon as I arrive.
"South Africa is a great rugby nation so the challenges ahead are huge but I am determined to give my all to the Lions cause."
Jenkins is due to arrive in South Africa after Wednesday night's fourth tour fixture with the Sharks and will link-up with the Lions in Cape Town on Thursday.
His appointment means Jenkins will go head-to-head with the record Springboks points scorer Percy Montgomery during the Test series after he accepted an invitation to join Peter de Villiers' coaching team as a kicking advisor. Montgomery made his Test debut against the Lions in 1997.