Keyword %question_answer_X_qY_file_id% does not return asset id

[vmu]

In my asset listing, this keyword returns a string on the lines of:
IMG_12345_11111.jpg, type image/jpeg, 1.8 MB, which exactly what a %question_answer_X_qY% would have returned. I was hoping for the asset id of the file that was uploaded.

Help please.

[Bart]

What version of Matrix are you using? This keyword was only added since 5.2.7.1.