The competition is run under the slogan "95% chance to win the best of British prizes" to reflect the claim by Ribena owner GlaxoSmithKline that 95% of all British blackcurrants are used to make Ribena.
Other prizes in the competition include 50 pairs of Virgin Mobile V Festival tickets and cuttings to grow your own blackcurrant bush. The aim is to better appeal to the product's key target audience of young adults.
The competition, which launches in March, is backed by PR, radio advertising, in-store promotion and a dedicated microsite at .
Jamie Maker, Billington Cartmell account director, said: "The 95% chance to win almost guarantees that consumers will win a prize. You'd have to be very unlucky not to win.
"This highly motivating promotion bucks the trend of typical instant lose promotions where there are usually so very few prizes on offer."
Billington Cartmell was also behind a 2004 campaign, called "Win a Donkey", which involved a link-up with 'Shrek 2' and offered the chance to adopt a donkey at a sanctuary as well as a chance to visit it.
The campaign won three gongs at last year's Marketing Communication Consultants Association awards.
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