grid lines on top of main plot lines

Hi,

Trying to make a simple 2D line plots that show a grid as thin grey
lines, I noticed that the grid lines are on top of the data lines. I
think this issue may have come up a while ago.

Anyway, digging through axes.py, it looked like a simple solution was
to change axes.py line 358
- self._axisbelow = False # todo make me an rcparam
+ self._axisbelow = rcParams['axes.axisbelow']

and an rcParam to __init__py line 788:
     'axes.axisbelow' : [False, validate_bool], # put the axis below lines

Then using
matplotlib.rc('axes', axisbelow=True)

worked as hoped. Is this a reasonable change? If so, can someone add this?
(for some reason I don't fully understand, I can't get svn to connect
to sourceforge from my main machine).

Thanks,

--Matt Newville