Though Adam's surname is clearly indicated as Harris, when we see his father's tombstone prominently in the forefront of the cemetery scene, it reads Farris.
While perusing the personals, Glen's left hand jumps from holding the paper on the side to the top between shots.
When Adam calls Glenn to tell him why he'll be missing Valentine's Day, he calls Adam's house phone and leaves a message in the answering machine. However, Glenn clearly has a cellphone that Adam has called in the past. The answering machine serves only as a plot device for Glenn to not get the message.