The Lebanese government is seeking to repair relations with Syria by new overtures. They come a month after the frail regime here was gripped by fear that Syrian support of opposition forces in September's civil warfare was aimed at toppling the government.

The Lebanese tactic is clearly aimed at smoothing troubled waters before a meeting in Geneva next week of the feuding Lebanese warlords and barons, which include Syria's allies. Syria and Saudi Arabia are to have observers at the conference.

On Wednesday, Lebanese President Amin Gemayel telephoned Syrian President Hafez Assad to invite him formally to send the observers. The call was their first direct contact in eight months. This evening, aides said Gemayel had intended to helicopter to Damascus to meet with Assad but the session was postponed for unexplained reasons.

Western observers familiar with the Gemayel government's thinking said its representatives to attend the Geneva session had decided to start by saying "encouraging things" to the Syrians. What specifically the Lebanese might offer was unclear.

Reports here and in Damascus described the 15-minute telephone conversation between Gemayel and Assad as friendly. "Let's remain in touch," Assad reportedly said at the end.

But whether the Damascus regime would act to foster compromise at the conference or whether it would choke off the uncertain efforts at achieving detente among Lebanon's divided factional leaders remained a mystery. Optimists were giving no odds on the outcome of the talks.

Lebanese opposition leaders were in Damascus earlier today and yesterday, where they met with Assad and his foreign minister before putting finishing touches on their working paper for the conference. The group, which included Druze leader Walid Jumblatt, former president Suleiman Franjieh, former prime minister Rashid Karame and Nabih Berri, head of the Shiite Moslem Amal militia, later left Syria for Geneva.

Apparently as an insurance policy against the collapse of the talks, Shiite and Druze militia in Lebanon have in recent days begun to rearm massively, according to western military officials and Moslems living in front-line communities.

The Lebanese Army has been rapidly refurbished with modern weaponry and ammunition bought from the United States and France. The tank force has been tripled to 150 in the last week, according to western officials. Helicopter gunships have been purchased and arsenals now contain five times the amount of ammunition they held at the outbreak of fighting in late August.

Numerous sporadic violations of the cease-fire agreement have become more worrisome as they have appeared to intensify in the last two days. Eighteen persons were wounded yesterday in a variety of clashes that involved the Army, Druze, Shiite and Christian militiamen.

Foreign military observers feared the clashes would heat up next week if the Geneva talks were stalled.

Perhaps the most difficult issue facing the conference is what to do about the May 17 Lebanese-Israeli agreement, which Syria and its allies have demanded be abrogated.

The Lebanese government is hoping to "finesse" the issue, according to western diplomats, although it is committed to honor the agreement. Negotiated under U.S. auspices, it cedes Israel special rights in southern Lebanon. American officials have been telling Lebanese that if it is canceled former defense minister Ariel Sharon and other hard-liners in Israel will become more obstinate toward Lebanon.

The agreement with Israel "is just going to have to be left quietly out there awaiting implementation," said a western diplomat. "There could be renegotiation, but I don't think it can be done now."

The basic hope is that the conference can achieve more a reconciliation of people than an immediate reconciliation of all the thorny disputes.

The United States hopes that it can lead to formation of a coalition government, bringing in the warring factions. They would proceed to deal with matters such as revising the country's 1943 national pact, which established power-sharing arrangements among the various sects.

U.S. Middle East emissary Richard Fairbanks is to attend the conference but without any defined role. Saudi Arabia announced yesterday its official observer will be Mahmoud Kuhami, its ambassador-designate to Lebanon. Syria has not said who would represent Damascus. There is speculation that it might be Ambassador to France Yusef Chgaccour.

What part, if any, the Soviet Union might attempt to play in Geneva was unclear.

The Soviet Embassy's charge d'affaires in Lebanon has had a series of meetings recently with Syria's allies and other West Beirut Moslems.

Said a western diplomat, "We hear it around that the Russians are bitching loudly that the Syrians are leading them around by a ring in the nose."