If someone has an older version with something other than "livelong day", I would like to see it.

Regarding the idea that "livelong" couldn't be the original word in the song ("I mean, has the word 'livelong' ever occurred anywhere else? No." and "Well, that's twice in 450 years" and "It really doesn't matter how many copy-cat versions with "livelong" in them ya'll quote."), consider the following:

From "Bold Robin Hood and the Three Squires" @displaysong.cfm?SongID=792

Go home, go home," said bold Robin Hood.
And weep no more to-day
And I will stand hangman this LIVELONG DAY
To hang the Squires all three."

From "Julius Ceasar" 1.1.38-40 (Shakespeare)

Marullus. Knew you not Pompey? Many a time and oft
Have you climb'd up to walls and battlements,
To towers and windows, yea, to chimney-tops,
Your infants in your arms, and there have sat
The LIVELONG DAY, with patient expectation,
To see great Pompey pass the streets of Rome.

From "I'm nobody. Who are you?" by Emily Dickenson

How dreary to be somebody!
How public, like a frog
To tell your name the LIVELONG DAY
To an admiring bog!

From "The Child-Christ on the Cross"
By Henry Nutcombe Oxenham (1819–1888)
   
The LIVELONG night, the LIVELONG DAY,
My child, I travail for thy good,


From "The Leaves Are Turning Red" (1 Oct 1853)
Canzonet
Written by Henry C. Watson
Composed by William Vincent Wallace, 1812-1865.

No more the summer's fervent heat,
O'ertakes us on our way;
We roam at will with tireless feet,
Thro'out the LIVELONG DAY!
We roam at will with tireless feet,
Thro'out the LIVELONG DAY!

Kent