“What did one Irish ghost say to the other?”/“Top o’ the moaning!”

“Top of the morning!” is a morning greeting. A St. Patrick’s Day riddle is:
 
Q: What did one Irish ghost say to the other?
A: “Top of the moaning!”
 
The joke has been cited in print since at least 2001.
 
   
Kidsjokes.co.uk (June 14, 2001)
St Patricks Day Jokes
What did one Irish ghost say to the other?
‘Top o’ the moaning!”
 
DISboards.com
Goofy’s….Galway Groans?....
Discussion in ‘Community Board’ started by Goofyposter, Mar 17, 2003.
(...)
What did one Irish ghost say to the other?
...........“Top o’ the moaning!”
 
Google Groups: alt.humor.jewish
Jest For Kids Weakly 03-16-04
Stan Kegel
3/21/04
(...)
What did one Irish ghost say to the other?
Top o’ the moaning!” (Tiger)
   
Orange Peel—Citrus Glen Newsletter (February 2006)
St. Patrick’s Day Groaners
Q: What did one Irish ghost say to the other?
A: “Top o’ the moaning!”
 
Twitter
Beverly Schmitt‏
@BeverlySchmitt
Q.  What did one Irish ghost say to the other?
A.  ‘Top o’ the moaning!
9:54 AM - 17 Mar 2009
   
Google Groups: rec.crafts.textiles.quilting
Re: Happy St. Paddy’s Day
Sandy E
3/17/10
Howdy!
What did one Irish ghost say to the other?
Top o’ the moaning to ya’!
 
ABC To Drawing
Saturday, March 12, 2011
>i>Smoke Pipe
What did one Irish ghost say to the other?
‘Top o’ the moaning!
 
HubPages
St Patricks Day Jokes and Riddles For Kids
Updated on March 26, 2012
(...)
What did one Irish ghost say to the other?
‘Top o’ the moaning!