Equipment failure

An old man went to the doctor’s to get a sperm count. The doctor gave him a jar and said; “Take this jar home and bring me a semen sample tomorrow.”
The next day, the old man reappeared at the doctor’s office and returned the jar. The jar was as clean and empty as it had been the previous day. The doctor asked what had happened and the old man explained…
“Well doctor it’s like this - first I tried with my right hand but nothing, then I tried with my left hand but still nothing. Then I asked my wife for help. She tried with her right hand, and then with left hand but still nothing. Then she tried with her mouth, first with her teeth in and then with her teeth out, but still nothing. We even asked Eileen, the lady next door, and she tried too; first with both hands then with her armpit. She even tried squeezing it between her knees, but still nothing.”
The doctor was shocked. ”You asked your neighbour?”
“Yep,” replied the old man, “and no matter what we tried , we still couldn’t get the jar open”