When J is not J: e-mail miscommunication

One of my customers seemed to had gotten into the habit of calling me "J". I got e-mails like "Nice work J!", "Copy and paste J!".

After about a year of this, actually triggered by the "Copy and paste J!" phrase in an e-mail today, I had to write back and ask if the customer was angry or frustrated about something.

It turned out that what arrived as "J" on my side had been a smiley on his side, but due to some incompatibilities between the e-mail systems, it became mangled into a "J" when I got it. Which by coincidence is of course the initial of my given name.  I had started to think that the customer had some deep seated passive aggressive anger issues.