From the BBC:
Before you fear too much for the decorum of old Auntie Beeb, this is what it’s about:
Around 1,000 fans arrived for the Ivory Coast tie in their traditional bright orange trousers – but bearing the logo and name of a Dutch brewery.
To protect the rights of the official beer they were denied entry, so the male fans promptly removed the trousers and watched the game in underpants.
Talk about a strict dress code..