The opposition has denounced the new court, saying any decisions by a tribunal stripped of independent voices had no credibility. Musharraf purged the court on Nov. 3 when he declared emergency rule, days before the tribunal was expected to rule on his eligibility to serve as president.
The United States has put immense pressure on Musharraf to restore the constitution and free thousands of political opponents jailed under the emergency before Pakistan's critical parliamentary election on Jan. 8.
Pressure of another kind was exerted by Pakistan on the United Arab Emirates, where foreign-based journalists of Pakistan's independent Geo TV have been broadcasting out of Dubai since Musharraf's crackdown. On Sunday Geo's news broadcasts were shut down.
In response, about 150 journalists and civil rights activists in Islamabad held protests against this latest action against the press.
Monday's court ruling could hasten Musharraf's decision to take off his army uniform. The general has said he would quit as armed forces commander by the end of the month, assuming he was given the legal go-ahead by the court to remain as president.
Chief Justice Abdul Hameed Dogar dismissed three opposition petitions challenging Musharraf's victory in a disputed presidential election last month, saying two had been "withdrawn" because opposition lawyers were not present in court.
The third was withdrawn by a lawyer for the party of opposition leader Benazir Bhutto, who suggested the court was illegitimate.
"We asked for (the case) to be postponed because we said there is no constitution," she told reporters in Karachi after a meeting with the U.S. ambassador. She said she had no plans to revive power-sharing negotiations with Musharraf, broken off after the general's decision to declare emergency rule.
"We are not going back to the former track," Bhutto said. "We are interested in a road map for democracy, but we do not have the confidence that Gen. Musharraf's regime could give us that road map."
At a protest in Islamabad, Omer Farooq, a journalist with AVT Channel, said the reconstituted court lacked credibility.
"This decision by the Supreme Court will not at all be taken seriously by anyone, anyone in the country, whether civil society, journalists, (or the) legal fraternity," Farooq said.
One of Musharraf's first acts after seizing extraordinary powers was to purge the Supreme Court of independent-minded judges. Opponents had argued that he ought to be disqualified under a constitutional ban on public servants running for elected office, which they said applied because Musharraf was still army chief.
The military ruler told The Associated Press last week that he expected the retooled court to quickly endorse his re-election, and he was right. Deliberations lasted less then a day on the most serious cases challenging Musharraf.
The court said it would rule Thursday on another petition from a man whose candidacy for the Oct. 6 presidential election was rejected by the election commission. Only then can it authorize the election commission to announce Musharraf the winner of the vote.