Ginuwine Can't Remember Justin Timberlake 'Acting Black' as Britney Spears Claims

Ginuwine's throwing water on at least one story from Britney Spears' memoir -- because he has no recollection of Justin Timberlake wiggin' out when they all ran into each other back in the day.

In "The Woman in Me," Britney claimed that JT royally her embarrassed when they were dating by throwing on a "blaccent" for Ginuwine -- going full-blown "fo shiz" with his slang. 🙈

Well, Ginuwine has a different memory of things ... telling People he's the same 'ol G he was back in the early 2000s, so he would've remembered Justin trying too hard to fit in, and would've questioned him on the spot.

Now, Britney also claimed *NSYNC intentionally mingled with Black artists, while the Backstreet Boys positioned themselves as a white group.

Justin hasn't responded to any of Britney's allegations about him -- but his *NSYNC buddies made it clear they have his back this year. They even returned to the Billboard charts with their new song "Better Place" for the 'Trolls' movie.