ugly arrow with xpdf

Hello,

when I create an arrow with

from pylab import *
subplot(111)
arrow(.5, .5, -.05, .02, lw=5, width=.01)
savefig('foo.pdf')

and view it with

  % xpdf foo.pdf

then I see on the startpoint an ugly pike. With gv and evince everything
is ok.

Any idea how to fix it in mpl? Because I dont want to switch to an other
viewer then xpdf.

Thanks,

  Friedrich