I've got a 1.5 PSP and it refuses to go to sleep mode after the PSP slash screen is displayed.
Seems like a cruel joke to me that is being used to trick people into upgrading to 2.6.
Try turning on your PSP with no UMD disc loaded in, then put one in and run it. When the PSP slash screen plays, try to put it sleep mode (after the music plays, but before the screen fades)
If it goes to sleep, then it MAY work. If not, it's just a joke.
If your PSP DOES go to sleep, then wait for someone else to actually try this little "hack".(hey, better them than you, right?)
Try this out and please report back!
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