TD5 lumpy tick over until up to temperature?

[DALESMAN]

I have owned my 2002 90 CSW TD5 for two weeks and love it . The only thing I am worried about is that until the engine is up to temperature the enging idle speed is very lumpy. It never stalls but it sounds like it wants to. Is this normal for this engine. I am greatful for and advice on this.
Cheers Richard.