I also once had a mechanic call me on my cell phone and verbally assault me. The reason? I wrote up something in the aircraft logbook when I wasn't on the ground in PTK (or LRD) where they had maintenance. He was pretty ticked that I had grounded the airplane because I decided against "finding out" about the issue after the trip was completed and the airplane was back home.
He ended the call with, "How long have you f@#*ing worked here, anyways? Because you're not going to last very long if you keep pulling s@#$ like this!"