Possible bug in annotate

Hi all,
I think there may be a bug in annotate. If I don't have any offset
between the xcoord of xy and xytext I get a zero division error.
Otherwise it is fine. For example:

In [3]: plot([1,2,3],[1,2,3])
Out[3]: [<matplotlib.lines.Line2D instance at 0x8cec96c>]

In [4]: annotate('hello', xy=(2.0,2.0), xytext=(2.0,1.5),


<type 'exceptions.ZeroDivisionError'> Traceback (most recent call last)


/usr/lib/python2.5/site-packages/matplotlib/patches.py in
getpoints(self, x1, y1, x2, y2, k)
    665 """
    666 x1,y1,x2,y2,k = map(float, (x1,y1,x2,y2,k))
--> 667 m = (y2-y1)/(x2-x1)
    668 pm = -1./m
    669 a = 1

<type 'exceptions.ZeroDivisionError'>: float division

It looks quite clear where the problem is. Though I'm not sure I'm up
to making a patch.