The lawsuits were jointly filed by the NSTP, which publishes the country's oldest English-language daily, the New Straits Times, and the group's top brass.
NSTP officials were unavailable to comment.
A media analyst said this would instil fear in a society already unaccustomed to open debate.
But he also said that bloggers should not post wild accusations.
"If the postings are defamatory, then bloggers are not exempted from facing the music. But one has to be very clear... it is a thin line between fair comment and defamation"
Zaharom Nain, Universiti Sains Malaysia
Zaharom Nain, a journalism lecturer at the school of communications in Universiti Sains Malaysia in the northern state of Penang, said the action could intimidate bloggers and other internet users.
"The community of bloggers in Malaysia is lively but still relatively small. They would feel intimidated even though the government guarantees no censorship of the internet under the MSC (Multimedia Super Corridor)," he told Al Jazeera.
The no-censorship rule is provided in the 10-point Bill of Guarantees under the MSC initiative that is designed to attract foreign investors.
Despite the official assurance, Zaharom says the country's defamation laws are applicable to those operating in the cyber world.
"If the postings are defamatory, then bloggers are not exempted from facing the music. But one has to be very clear ... it is a thin line between fair comment and defamation.
"This development is worrying and I see it as a threat to the political debates we see on the internet."
The court will hear the inter parte application for Ahirudin on January 25 while Ooi’s will be heard on January 30.
Political discussions are more vibrant on blogs and online forums than in other media due to tight legal controls and self-censorship practised by the state-controlled media.
"They are testing the boundaries of expression and the web is the last frontier," Zaharom said.
"Some people will be afraid to voice out their thoughts online as we move closer to the general elections next year."
Malaysia was known to use anti-press and defamation suits claiming millions of dollars to silence government critics in the 1990s, he said.
"I believe that was the case then ... it still is now."
But Raja Petra Kamarudin, editor of Malaysia Today, another popular political website, said being sued should not deter people from blogging.
"I'm not taking this as a big issue. It's no big deal ... being sued is normal because some people were unhappy over the postings.
"But let's see what happens in court. That would be the most interesting part."