The problem was brought to my attention back on 12-Sep-2013 by Michael Lovett with ticket #IT00003112:

"When Pam goes to print and save a Data Quick as an Adobe doc the words are all scrambled."

I found out that what they were doing was selecting all (Ctrl-A), then (Ctrl-P) to print and finally selecting the PDF printer and generating the PDF file. It had the strange characters indeed.

But there was a Print button on the form, and if printed this way the strange characters wouldn't show up. This method was discarded because they needed a date stamp, and the only way to generate it was by selecting all and printing.

So, I did some research and came across an Adobe forum (http://forums.adobe.com/message/3973407) in which somebody suggested the following:

I believe I have found a fix to the problem. I had a client who would
only get the strange characters in the PDF's when they printed in
Internet Explorer but Chrome would work fine (for reference they were
running Win 7 64bit and Adobe Pro 9 I believe). If you go into the
Control Panel/Devices and Printers/Right Click on Adobe PDF printer and
choose printing preferences/Uncheck the box to "Rely on system fonts
only; don't use document fonts". That should fix it for you.

I followed the suggestion and it works now. See attached screenshot.