'uneven' acceleration

All,
I am fairly new to the Alfa world - bought my first used 156 1.8 petrol
(t reg - 1999) about 3 weeks ago.
A strange thing I have noticed however, is the uneven acceleration I get
in 2nd. If I move off, up into 2nd and then floor it (or even just get a
little enthusiastic with the throttle), the car picks up slowly until it
hits about 3000 rpm and then takes off ! Is this slight delay in power
normal, or should I be looking for a problem that would cause it ??