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Justin Bieber is famous for his tunes, but his Tweets took center stage and got people talking this weekend.

Most eye-opening was one aimed at Mariah Yeater, the woman who accused him of fathering her child.

On Saturday Bieber tweeted: "Dear mariah yeeter (sic) …we have never met…so from the heart i just wanted to say" and then he posted a link to a YouTube audio clip of the character Borat, played by comedian/actor Sacha Baron Cohen. In the clip, Borat says, mockingly: "You will never get this. You will never get this. La la la la la …"

His fans - known as "Beliebers" -  re-tweeted the original tweet more than 53,000 times, and many of them found it very funny.

"I still cannot stop laughing over Justin's tweet to Mariah. LOL," one user Tweeted. Another wrote: "JUSTIN DESERVES A GRAMMY FOR HIS LAST TWEET. Mariah Yeater, you will never get this" and another added: "Dear Mariah Yeater , DID YOU LEAVE YOUR STOVE ON? CAUSE YOU JUST GOT BURNED! lol . Sincerely Beliebers"

They also commented on his misspelling of her last name. One fan wrote: "It's not Mariah Yeater anymore, it's Mariah Yeeter cause Justin said it was."

Last year Yeater, 20, stunned the entertainment industry and Bieber's millions of ardent fans when she sued the the pop star, claiming she got pregnant after they had minutes-long tryst in a backstage bathroom following one of his concerts.

Bieber, now 18, steadfastly maintained the incident never happened and said he had never met Yeater. The woman abruptly withdrew her lawsuit, but said she wanted to settle out of court.

Bieber reportedly took a DNA test to disprove the paternity claim.

Bieber posted the tweet during what he called Random Twitter Hour, which, not surprisingly, featured other odd postings, including: "Rick james is my grandfather"; "my loins"; "chuck norris wears justin bieber pajamas"; "why does david ortiz look like robocop haha" and "wish dirty diana would clean up her act."

The stream-of-consciousness style of the tweets had some fans concerned.

"WHAT IS WRONG WITH YOU ARE YOU DRUNK?" one fan asked. Another said: "JUSTIN BIEBER IS DEFINITELY HIGH RIGHT NOW."

Other fans embraced it.

"I love when Justin does RANDOM TWITTER HOUR.  It's so freaking cute," one fan tweeted.

But longtime publicist and ABC News consultant Howard Bragman wasn't so unconcerned.

"Most of the time his random tweets are cute and clever and something his fans really enjoy, but I have to say this latest tweet against the woman who filed the paternity suit against him is just way off base, and it's taking him a couple steps backward in his career as opposed to moving forward," Bragman said. "Why would he bother to bring this up when it seemingly has gone by the wayside? And what I think it's evidence of it's something that really bothered him deep down and continues to bother him."

Bieber last week released a sneak peak of the music video for his new single, "Boyfriend." In it, the pop star unveiled a more mature image.

But tweeting about Yeater wasn't wise, Bragman said.

"Anybody can understand him being frustrated with the person who likely made some false charges against him, that we're all clear on, but conventional PR wisdom is you don't respond to things like this," Bragman said. "And most of the time Justin Bieber's really wise about his marketing, his tweets and his messages, and sometimes you realize … that he's a teenage boy and it shows."