The actor will be halfway through filming the new James Bond film The Quantum Of Solace when he reaches the landmark birthday on 2 March.
'I was a pain in the arse at 30. I didn't know what I wanted to do. I couldn't commit. Not much has changed,' he says.
'My 40th is in the middle of Bond, but I'll celebrate it as best I can because I've got a feeling that 49 is going to come around really quickly.'
Despite getting older, Daniel has ruled out ever going under the surgeon's knife.
'If it starts to drop, it starts to drop. No one likes to get old and sag, but surgery isn't right,' he tells the Daily Express.
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