What is the origin of the expression "piss up a rope"?

Dear Tina 

This experssion originated in America, during the early 20th century.
Cassell's Dictionary of Slang only mentions "originally US, 20th
century"; Chapman?s Dictionary of American Slang is a bit more
revealing:
"[...] by 1940s Go away and do something characteristically stupid;
=?get lost,? ?go fly a kite?: ?He asked for another contribution and I
told him to go piss up a rope.?"
(SOURCE: Answer by Ken Greenwald, "piss up a rope", Wordwizard, 
December 21, 2002 <http://www.wordwizard.com/clubhouse/founddiscuss.asp?Num=3740>).

As for the usage in other English-speaking cultures (outside the US),
it should be noted, that all of the books listed in Amazon.com with
this term seem to be American or to quote Americans.

Amazon search: "piss up a rope"
<http://www.amazon.com/exec/obidos/search-handle-url/index%3Dstripbooks%26rank%3Drelevance20041029rank%26field-keywords%3D%252522piss%252520up%252520a%252520rope%252522%26store-name%3Dbooks/102-4045442-5952114>
.


There is no answer here, but it is still an interesting thread: 
Ask Metafilter January 19, 2004 [No Title] 
<http://ask.metafilter.com/mefi/4754#107132> - Warning - some readers
might be offended by the language used in this thread.

I hope this answers your question. Please contact me if you need any
clarification on this answer before you rate it.

Search terms: 
"piss up a rope" + origin/dictionary/slang

It came from ----- the guy at the top of the rope.

First uttered by a Glaswegian bricky by the name of Jimmy McBauchle in
1928 to his brother who owned a chip shop in Byres road -- the same
chip shop where Elvis now works. It was occasioned by a request that
he help gut haddock fillets on a Friday night when any respectable
Weegie is getting legless in a quaffing hostelry. It was also repeated
by said Jimmy later that night when he quipped, ?You waanted me to dae
the guttin, weel I got guttered instead, ya bas,? just before he
passed out.

Honest

My late father-in-law, who was Canadian, used a variant: instead of
"go piss up a rope," he would say "go piss up a stump." Once I asked
him about the phrase, and he said he'd learned it while he was an
officer in the Royal Canadian Air Force. I doubt that it's official
military terminiology, though. ;-)