Jonathan Ross was forced to apologise to his radio listeners after guest Rupert Everett swore live on air.
Ross landed in trouble for swearing on Red Nose Day
Everett was appearing on Ross's BBC Radio 2 show to plug his autobiography, Red Carpets and Other Banana Skins.
Ross had to remind Everett to watch his language and both apologised for the use of the "f-word".
A BBC spokeswoman said about 20 complaints had been received following the broadcast on Saturday morning.
The show has not been made available to listen to again via the Radio 2 website.
Earlier this year, Radio 1 breakfast show presenter Chris Moyles landed in trouble for swearing live on air and using an unacceptable derogatory term.
The station said it was going to introduce fines for DJs who swore on the air, after broadcasting regulator Ofcom ruled it was unacceptable for children to hear swearing on the radio.
Ross himself was rapped by Ofcom in 2003 after he swore during a Red Nose Day live broadcast.