Jack's gesture of arranging to have a red rose sent to Mary every day after his death is the subject of this page on the snopes Urban Legends site called "Posthumous Roses":
http://www.snopes.com/glurge/benny.asp. Someone wrote an overly sentimental poem ("glurge" as snopes calls it) on the subject, and Barbara Mikkelson, the co-creator of the web site, sets the recond straight with the real story about Jack. She missed the fact that Jack's birthday was on Valentine's Day (in the poem, that's the only day the rose arrives each year), but I've emailed her.