No, no. Hank is short for Henry.
according to my birth certificate Harry stands for Harry
It doesn’t look any shorter.
There is some connection between Harry and Henry (what it is, I don’t know). I’m pretty certain that Diana and Charles’ second son, Prince Harry as he is known to the public, is actually named Henry.
Here’s a thread on name abbreviations.
http://www.straightdope.com/ubb/Forum4/HTML/004335.html