As the Labour Party Conference continues this week I can't help but feel that something is missing.

Is it Tony Woodley, Joint General Secretary of Unite, tearing up his copy of the Sun? No, he's present although he's mellowed out and is instead using his time at conference to rail against the government's cuts rather than its press supporters.

Is it Lord Mandelson getting a standing ovation from the Labour faithful? Well it could be, but since the publication of his memoir, The Third Man, the so-called Dark Lord is unlikely to have many fans at Labour conferences any more.

No. What's missing are the Liberal Democrats. Since the Lib Dems committed the ultimate sin for left-thinking people of getting into bed with the Tories in May, Labour claims to have gained an extra 35,000 members, of whom a third voted Lib Dem at the general election.

So why is it that of the 10,000 ex-Lib Dems that have now joined the Labour Party none or few of them can be found to speak at conference?

What could be more damaging for the Coalition Government, and the Lib Dems in particular, than to have delegate after delegate come up on stage at the Labour conference and on live TV saying, "I voted to keep the Tories out", "I voted against a VAT rise", "I feel betrayed by Nick Clegg"?

And yet almost everyone speaking on the main stage at Labour Conference seems to be a stalwart Labourite or trade unionist.

Are Labour exaggerating the defection of Lib Dems? Are these converts just shy? Are they considering a return to their former party? Whatever the reason, the scarcity of former Lib Dems at the Labour conference is surprising.