Well, it is an odd mistake to make. But do you really think they would jeopardize their own release like that? It would be interesting if you could find where you originally read about this.
Unfortunately I’m starting to think it was discussed at the SWWB back in 2005 or 2006. Which means nothing is left to find.
I actually have hundreds of messages saved from that time, but I couldn’t find anything from them… which isn’t surprising as I was too lazy in saving the messages and missed probably hundreds of them that should have been saved.
It is very unfortunate that board works the way it does because over the years (during the time of this forum and the many years before this) there have been lots of good information there that can’t now be found anywhere.
Anyways, I emailed someone who might know about the music thing. I’ll let you know if I get an answer. 
EDIT: Maybe it’s like one of those porn movie frames appearing in a disney movie or something… prank or something by an unhappy employee. 
Cannot understand why people use SWWB. This place you have a better chance of finding stuff.
Here is the Italian version of the main song: http://www.youtube.com/watch?v=D6FKzvCqK08
Surely this should have been used with the Italian dialogue? Having said that, it sounds to me that the lyrics are “sempre” (always) rather than “never” so I guess it still may not have tied-in. I’ll have to check what Cuchillo is saying in the Italian dialogue.
My weekend haul of SW 
Resulted in a bit of doubling, but it’s all good! 
The Fast the Saved The Damned Box
Dorado Films version of Django Shoots First
a non-public domain version of Massacre Time clocking in at 92 minutes
Spaghetti Western Bible Vol 1: Trinity
SW Comp featuring A Genius Two Partners and a Dupe Massacre at Grand Canyon and Boot Hill