Both Edwards and Hennessey, who joined Palace from Wolves in January 2014, are part of the Wales team who have booked their place in the Euro 2016 finals.
Wales confirmed their place in the Euro 2016 finals on Saturday evening, despite a 2-0 defeat to Bosnia and Herzegovina away from home in a Group B qualifier.
The Dragons are second in the group at the moment with 18 points from nine matches, just two points behind leaders Belgium.
This is the first time that Wales have qualified for a major international competition since 1958.
It now remains to be seen if Chris Coleman’s side will progress to the Euro 2016 finals as Group B winners. Wales have scored just nine goals and conceded only four in nine qualifiers.