[R] line plot through NA

[rggefrm at ucl.ac.uk]

Dear R-help list,

I hope I did not miss something obvious, because my question seems very 
simple, but I couln't figure out how to do it.

If I have the following data:
Day<-c(1,2,3,4,5,6,7)
V<-c(5,NA,10,30,45,NA,10)
than the line in plot

plot(V~Day, type="b")

will start with the 3rd value and stop stop at the 5th value because all NA 
are omitted. Is there now a parameter which can be added to the plot 
function so the line will start with with the first value and skip the NA 
values and can this than applied to xyplots.

Many thanks