A management meeting at Radio One yesterday, attended by the station's controller Matthew Bannister, decided to take the initiative and pounds 2,000 was paid for the prime site.
The sign flashed the words: "Wanted. Radio One breakfast DJ. Must work five-day week. Ginger hair an advantage. Apply 97-99 FM Radio One."
A Radio One spokeswoman denied last night that the joke sign was a waste of licence-payers' money, saying that the corporation had managed to secure a particularly advantageous rate.
Evans gave in his notice on Thursday after being refused permission to reduce his working week to four days and take Fridays off. The ginger- haired presenter also hosts the Channel 4 programme TFI Friday on Friday evenings.
Yesterday Evans returned to the offensive on his Radio One breakfast show. He admitted the dispute had left him feeling sad but he refused to withdraw his resignation, even though fellow DJ Simon Mayo urged him to stay on.
He told listeners: "I'm a little forlorn," during the 9am handover to Mayo. But his admission came after he provocatively chose to play songs including "Please Release Me, Let Me Go" and another which featured the lyrics: "Give me something before I splutter out".
In a bizarre handover, Mayo told him: "Change your mind." Evans said: "What do you mean?" - to which Mayo replied: "Change your mind." Evans then said: "I can't because I can't have Fridays off."
Mayo told him: "Well convert to Islam. Friday is a holy day. You can convert to Islam and say `Look, it's a religious point, now you have to give me Fridays off'. Why don't you do Sundays to Thursdays?"
Evans replied: "No, it's still six days a week."
Then Mayo said: "I've just remembered - Matthew said don't talk about it on the handover."
Evans had also used his programme to appeal for another job. This appeared to have paid dividends as later in the day the commercial station Talk Radio revealed that it was going to offer Evans pounds 1m to work for them.
A spokesman said: "A request has been sent to his agent and we hope negotiations are going to start soon. Everything is negotiable. Chris would find the perfect format with us. He is a brilliant talker and would be great for the station.
BBC executives will now have to consider whether it is worth keeping Evans on until the end of his contract on 27 March with the risk that he will use his remaining shows to make comments about the corporation.
The station's spokeswoman said last night: "We're not unhappy about what he said on his breakfast show. Chris is a spontaneous broadcaster but we will look at each incident individually and if we feel there is one we need to talk to him about then we will do so."
Evans, who earns more than pounds 7,000 a day for his outspoken brand of broadcasting, told listeners: "In the middle of last summer I asked for Fridays off because we have got to do the TV show.
"... I went to them last summer because I didn't know if the TV show was going to be a success or not.
"Getting up to do the show is not a big deal, I'm not saying it's hard work, but what I wanted to do was have a nice day on Friday, do my TV show and get into work at 11 o'clock full of energy for 6.15, work till about 8 and that's it.
"So I said `Please can I have Fridays off, let someone else do the show'. In America it is common practice for a DJ to do Fridays, Saturdays and Sundays. That's all I wanted.
"In November I went back and asked for the same deal. I said: `Come on it's not working out, it's too long a week and I don't have to do it. Please', I said.
"They said we'll give you more weeks off next year. OK, so I now got 12 weeks off."
Evans then explained why he went back again to ask for Fridays off.
He said: "This Christmas I've had a great time. We did one TV show without having to get up at 5am each morning. I asked again and the answer is still no.
"I love to work on the radio, I absolutely adore it. It's my favourite thing in the whole world, although I admit we get paid an absolute fortune.
"We wanted to be here from Monday to Thursday but apparently that's not good enough. That's the whole thing, that's absolutely true. We are being forced out, that's it. "If somebody else wants to offer us a job Monday to Thursday we'd love to do it."
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