[R] Grouped bar plot

[jctoll]

Hi,

I am trying to produce a grouped bar plot from a data.frame and I'm
having difficulties figuring out how to do so.  My data is 500 rows by
4 columns and basically looks like so:

> head(x)
    V1        V2        V3        V4
1  XOM 0.2317915 0.1610068 1.6941637
2 AAPL 0.6735488 0.7433611 0.1594102
3   GE 1.2554160 0.9237384 1.6767711
4  IBM 1.6296938 0.3730387 0.5858115
5  CVX 0.9194169 0.4785705 0.1803601
6   PG 0.7768241 1.7622060 0.7640163
 . . .

I would like to produce something similar to what is found at:
http://www.statmethods.net/graphs/bar.html          # the grouped
barplot example
or
http://had.co.nz/ggplot2/geom_bar.html                # the Dodged bar
charts example

Across the X-axis, for each set(row) of 3 data points(V2, V3, V4)
associated with a symbol(V1), I would like to create a group of 3 bars
reflecting their values.  So the Y-axis will represent the magnitude
of values in the columns (V2, V3, V4), and X-axis will have 500 groups
of 3 bars, for a total of 1500 bars.  I would like the color of each
bar to reflect the column of data it represents, and to label each
group of 3 with the corresponding symbol in column V1.

I was trying to get this to work using ggplot but the y-axis in the
example is the count, which is not what I'm after.  Any suggestions,
to get me started down the right path would be appreciated.  Thank
you.

James