Footage broadcast on state television showed the dictator clad in black and wearing sunglasses, speaking to officials in a meeting room. However, he was not heard speaking.
The footage showed yesterday's date on a television screen close to Gaddafi.
Meanwhile, a series of Nato strikes targeted Tripoli early today.
Four explosions in quick succession were heard, preceded by the sound of loud whooshing - normally associated with cruise missiles.
After the strikes, the sound of speeding ambulances was heard by reporters staying in a Tripoli hotel.
The latest attacks came after the opposition claimed to have captured the airport at the key western city of Misrata, driving back troops loyal to Gaddafi.
Witnesses said hundreds of people celebrated in streets that were littered with burning government tanks [Ron: Hundreds of people?! Misrata is said to have 500,000 to 700,000 inhabitants. Where are the rest?]
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