Will Ferrell wasn't part of the initial 'Wedding Crashers' script.

The 52-year-old actor made a memorable cameo as funeral crasher Chazz Reinhold towards the end of the 2005 comedy film - which starred Vince Vaughn and Owen Wilson - and while director David Dobkin has revealed the character wasn't initially part of the movie, he believes Ferrell's small part was a ''rocket boost'' for the motion picture.

He said: ''Vince and Owen and I did about three weeks of work on the script before we started shooting, where we'd go through and improv the scenes and create ad-lib stuff and kind of rewrite those scenes.

''This scene wasn't in the movie, and there was a moment when Owen was like, 'Wouldn't it be funny if we crashed funerals?'

''It didn't really fit in that opening montage, and then later when I was looking for an all is lost moment I said, 'Owen, what if you go see Chazz? You mention this guy Chazz and we never see him in the movie.

'''What if you wanted to go see this guy to get some advice and he was crashing funerals? And you think all of this sounds really dark and you're really at your bottom, but when you go with him and you're at the funeral, it feels all wrong and you realise you should be by your friend's side.'

''And so Owen kind [of] went and wrote that scene.''

The movie tells the story of Wilson's character John Beckwith and Vaughn's Jeremy Grey, who crash weddings, but Dobkin admitted the marketing team were struggling to sell the film as a ''romantic-comedy'' until he corrected them.

Speaking to Entertainment Weekly, he added: ''Once we finished the movie, I remember with the marketing campaign they were like, 'Look, we don't know how to sell this.'

''They were cutting the movie to look like a romantic comedy and I was like, 'That's not right, this is a movie about sex and men growing up - it's a coming-of-age story ... for 35 year olds.''

Ferrell - who teamed up with Dobkin on this year's 'Eurovision Song Contest: The Story of Fire Saga' - recently teased there could be a 'Wedding Crashers' sequel.

He said: '''Wedding Crashers 2', yeah. I think we can just say it's being written.''

Ferrell also joked: ''How about if it's just the lawyers representing everyone in divorce court? And just make it like a legal courtroom drama, not funny at all.''