Another great job by the UN:

Hezbollah refused to disarm and withdraw its fighters from the battle-scarred hills along the border with Israel on Tuesday, threatening to delay deployment of the Lebanese army and endangering a fragile cease-fire.
[…]
Hasan Nasrallah, the Hezbollah leader, had insisted that any disarmament of his militia — even in the border area — should be handled in longer-term discussions within the Lebanese government, according to government ministers. But the Lebanese army, backed by key political leaders, refused to send troops into the just-becalmed battle zone until Hezbollah’s missiles, rockets and other weapons were taken north of the Litani River, the ministers said.

At stake in the standoff was implementation of a crucial provision of the U.N. Security Council cease-fire that went into effect Monday. The accord called for quick deployment of 15,000 Lebanese army troops south of the Litani River along the border with Israel. They were to take up positions under the aegis of a reinforced contingent of the United Nations Interim Force in Lebanon, or UNIFIL, to form a peacekeeping corps with a total strength of about 30,000.

Hezbollah’s reluctance to get its men and arms out of the border zone reflected nervousness over the continuing presence of Israeli soldiers on Lebanese soil. But it also demonstrated the militant Shiite Muslim movement’s increased assertiveness here after a war of more than a month during which it stood off the Israeli army while Lebanon’s national army stood aside.

I think the answer is that it probably has more to do with their positioning themselves for their next attack on Israel. Lebanon can’t control Hezbollah, they don’t even want to attempt to do it and this proves it. Hezbollah will not be disarmed and anyone who thought that this “peace” treaty would disarm them is a fool.
Then there’s this:

On the ground, Hezbollah’s militia and social welfare infrastructure were the only things still functioning in dozens of devastated villages across the border zone. Army troops in the village of Srifa, for example, were seen working under the orders of Hezbollah militia officers during a search for bodies buried under the rubble of buildings destroyed by Israeli bombing.
“What are the alternatives you have come up with?” Nasrallah asked. “Can the Lebanese army and the United Nations troops step up to the plate to defend the nation? Haste and simplification are out of the question. We were ready and will always be ready for dialogue to extend the authority of the state. We are part of the government and a basic part of it.”

This reads like an apologetic for Hezbollah keeping their weapons, they need them against Israel since Israel is an aggressor. The whole article is an apologetic, we know what side this reporter is on. Pretty objective reporting.
Read the rest of the article here. Go read the rest because the whole article is slanted toward Hezbollah.