For some values (related to multiples of .3 and .7 it seems) drop the last tick label.

expected: the last tick to be labeled, spacing of .1 between major ticks
get: all be last label are correct

The following demonstration is assumed to be in an interactive shell with pylab imported

fig = figure()
ax = gca()
draw()
ax.get_yaxis().set_major_locator(matplotlib.ticker.MultipleLocator(0.1))
ax.set_ylim([0,.2]); draw() # works
ax.set_ylim([0,.3]); draw() # fail
ax.set_ylim([0,.4]); draw() # works
ax.set_ylim([0,.6]); draw() # fail
ax.set_ylim([0,.7]); draw() # fail
ax.set_ylim([0,1.2]); draw() # fail
ax.set_ylim([0,1.4]); draw() # fail

tested against master branch.

In [17]: matplotlib.version
Out[17]: '1.2.0rc2'

using QT4Agg with PyQT4