(Novice-) Problem with the plot-function

Hello,
i have written this little function to draw different normal distributions:

n.Plot <- function(x,my,sigma) {
e <- exp(1)
names(x) <- x
f.x <- (1/(sigma*sqrt(2*pi)))*e^(-1*(((x-my)^2)/2*(sigma^2)))
plot(f.x,type="l",xlim=c(-5,5))
return(f.x)
}

if i define x like this:
x <- seq(-5,5,0.01)

Now 
n.Plot(x,0,1) 
DOES draw the correct plot, but the x-axis is labeled from 0 - 1000.
If i give the plot function the xlim=c(-5,5) option, the plot is only drawn 
for the first 5 values of x.
How do i tell plot not to take the indices of x, but the values (or their 
range) of x for labeling the x-axis ?