Newbie asking for axis labeling advice

This is James Phillips of zunzun.com, I'm mostly finished
with converting the site from DISLIN to matplotlib. I ran
into an axis labeling question and do not know the best
way to solve the problem. If someone more experienced
with matplotlib can advise me, I will be most appreciative.

If I construct a simple scatterplot, depending on the
magnitude of the values being plotted the Y axis label
can be pushed off the graph. For example, in the first
scatterplot below the Y axis label is fine yet in the
second it is pushed off the plot - ostensibly by the
larger values on the Y axis data label as the plot limits
are forced to be identical.

import matplotlib
matplotlib.use('GTKAgg')
import pylab

pylab.xlabel('X Data', multialignment='center')
pylab.ylabel('Y Data', multialignment='center', rotation=90)
pylab.scatter([0.1, 1.0], [0.1, 1.0])
pylab.subplots_adjust(left=0.07)
pylab.show()

pylab.xlabel('X Data', multialignment='center')
pylab.ylabel('Y Data', multialignment='center', rotation=90)
pylab.scatter([1000, 5000], [1000, 5000])
pylab.subplots_adjust(left=0.07)
pylab.show()

Since I will not know in advance the values users are
plotting, I cannot directly set the plot limits as
far as I know. Any advice on how best to handle
this problem? I could try to calculate a best limit
for each plot, or simply use a single large value such
that the Y axis label is never pushed off the graph.
Any other advice or ideas?

     James Phillips
     http://zunzun.com