Proposed patch for Python 2.7:

"""
--- util.py.old 2011-12-12 01:34:04.412234183 +0100
+++ util.py     2012-01-17 15:15:23.262257886 +0100
@@ -12,6 +12,7 @@
 from distutils.spawn import spawn
 from distutils import log
 from distutils.errors import DistutilsByteCompileError
+import platform
 
 def get_platform ():
     """Return a string that identifies the current platform.  This is used
@@ -76,6 +77,7 @@
         if release[0] >= "5":           # SunOS 5 == Solaris 2
             osname = "solaris"
             release = "%d.%s" % (int(release[0]) - 3, release[2:])
+            machine += ".%s" %platform.architecture()[0]
         # fall through to standard osname-release-machine representation
     elif osname[:4] == "irix":              # could be "irix64"!
         return "%s-%s" % (osname, release)
"""

So now the directory is named like "lib.solaris-2.10-i86pc.32bit-2.7".

Please, review.

I will commit it to 2.7, 3.1, 3.2 and 3.3 in a few days.