WARSAW -- Poland's communist leadership, inspired by the example of Soviet chief Mikhail Gorbachev, is preparing to launch a major new program of economic reform, but the country's failure to resolve the deep political conflicts of the Solidarity era is dampening hopes for meaningful change, according to government officials and political activists here.

After months of remarkably open national debate, a government commission is due to present a broad plan for changes in the socialist economic system next month that should, at least in theory, rank Poland among the leaders of such East Bloc reforms.

Drawn up in the face of long-lasting economic stagnation, the program represents the first comprehensive reform effort in Poland since the banning of Solidarity, the independent trade union movement. Government officials say it will fundamentally change the nature of communist rule in this key Warsaw Pact country, decentralizing power and significantly expanding opportunities for private enterprise.

"There are going to be great changes in Poland in the last quarter of this year," said government spokesman Jerzy Urban, "above all in the economic sphere, but also in political life. We are studying the future in Poland of socialism and the form it will take."

Western diplomats and activists of Solidarity, which still functions in semiclandestine form nearly six years after its suppression under martial law, agree that the new plan is ambitious. But like some associates of communist ruler Gen. Wojciech Jaruzelski, they question whether it will be possible to implement the reforms in the face of stiff resistance from an entrenched bureaucracy and a distrustful society.

It is generally acknowledged by government leaders that the last reform program, adopted in the last weeks of Solidarity's legal existence in 1981, never was effectively carried out. Published government polls show that most of Poland's 38 million people do not believe that further reforms by Jaruzelski's government will improve the country's situation.

Jaruzelski, analysts here say, continues to be haunted by the political legacy of his suppression of Solidarity. Without the help of the union, its followers, or the Roman Catholic Church, the government can have little hope of making Polish society believe in its policies, they say. Yet without public support, critics say, the Jaruzelski team may be too weak to successfully implement even well-designed reform plans and get the country working again.

"Jaruzelski will probably attempt far-reaching changes. But he is totally blocked and hemmed in politically," said Bronislaw Geremek, a leading adviser to Solidarity leader Lech Walesa.

"Jaruzelski supports Gorbachev's ideas. But he does not know how to realize glasnost, or political opening, in Poland without Solidarity. And he is not willing to try it with Solidarity because he is afraid of losing control of the country."

The course of reform in Poland is particularly important because Jaruzelski has emerged as the most enthusiastic supporter of Gorbachev and his policies in an Eastern Europe otherwise ruled by veteran traditionalists.

While neighbors such as Czechoslovakia and East Germany have appeared half-hearted, or even openly resistant, in following Gorbachev, Jaruzelski has attempted in the last six months to use the climate of renewal created by the Soviet leader to break the longstanding stalemate in Polish political and economic life.

The momentum for economic reform began to gather when Jaruzelski, eager to refute charges that his economic policy consisted mainly of ordering periodic consumer price increases, ordered a special commission in March to draw up a comprehensive list of proposed revisions of the economy.

Since then, several leading Polish experts on economic reform, suddenly invested with power after years of standing on the sidelines, have prepared detailed measures that are to be presented next month in the parliament.

Some of the steps are familiar from policies carried out in Hungary and China that seek to use market tools of capitalism to make the economy more efficient. Poles may soon be allowed to buy bonds and even stocks from state companies, for example, and the state monetary monopoly is to be broken up next year into a western-style, nominally competitive banking system.

Several aspects of the Polish plan, however, make it at once more daring and more difficult than reforms attempted elsewhere in the East Bloc. According to government officials, it will involve a significant expansion of private enterprise, easing controls on private businesses and allowing joint ventures between state and private firms in areas ranging from electronics to auto parts. This move is likely to draw stiff resistance from communist ideologues as well as workers who resent inequalities of income.

The other special task faced by Jaruzelski's planners is ending chronic shortages of raw materials, energy and consumer goods by balancing supply and demand. In many cases, this will require steep price increases and tough controls on wages -- austerity measures that have been repeatedly, and successfully, bucked by Polish workers during the past five years.

"Even if we assume that the most radical version of the reform is adopted, the question arises of how they are going to do it this time," said Leszek Balcerowicz, a professor at Poland's central school of planning, "because if the practice since 1981 holds true, they won't be able to stick to any tough measures."

Fear of a confrontation with workers has caused Jaruzelski to back down from reforms of wages and prices repeatedly since 1982. This year, for example, authorities vowed to limit wage growth to 12 percent, but they have allowed 26 percent so far, giving in to militant workers in factory after factory.

At the same time, fear of what political democratization could lead to has seemed to check the government from measures such as a dialogue with the church or Solidarity that might persuade workers to accept sacrifices.

Seemingly aware of their political quandary, communist leaders have taken steps over the past year meant to broaden support for their policies without making concessions to the opposition. Censorship has been eased, and a lively press debate on economic topics is now almost completely unhindered. Travel regulations have been relaxed and Poles have been told they may be able to get permanent passports for western trips beginning next year.

Since June, the government has taken cautious steps toward allowing public activity independent of the communist party, sanctioning an independent monthly magazine and "economic associations" formed in Warsaw, Krakow and two other cities to lobby for and assist private enterprise. According to a senior government official, more political steps are being considered to expand pluralism, including changes in the constitution.

Nevertheless, Solidarity activists, who say they believe that Gorbachev's preoccupation with reform in the Soviet Union means that Polish leaders are virtually free of past Kremlin constraints, say Jaruzelski's failure to look for a dialogue with the opposition is a crucial failing.

"I think Jaruzelski is failing to take advantage of the situation that exists now in the East," said Gabriel Janowski, a rural Solidarity leader. "He has an enormous opportunity now to look for a real political consensus in Poland, to come to terms with society. But he's unwilling to act."

While disputing this assessment, government officials concede that they have a difficult political struggle ahead. "Not all elements of the reform are going to be popular at first," said one senior official.

"And words won't help because Poles don't believe in plans and proposals anymore. People will support us only when they see reform beginning to change their lives, when they see more goods in the shops and more pay for hard work. We must try to make people see how the reform will be good for their own interests."