[R-sig-Geo] pretty in spplot()

[Tord Snäll]

Dear all,
I would like legend cut-offs that are prettier that just executing
spplot(SpatialPolygonsDataFrame(karta, 
as.data.frame(resdf[,c("TempEst.t","TempEst.tM1")])))

I try
spplot(SpatialPolygonsDataFrame(karta, 
as.data.frame(resdf[,c("TempEst.t","TempEst.tM1")])),at=pretty())
, though without sucess.

Could someone give a clue on how to do it?

Thanks!

/Tord