Allow docs to be built with Sphinx 0.5.x.
diff --git a/Doc/tools/sphinxext/pyspecific.py b/Doc/tools/sphinxext/pyspecific.py
index 018f4ac..48ce6da 100644
--- a/Doc/tools/sphinxext/pyspecific.py
+++ b/Doc/tools/sphinxext/pyspecific.py
@@ -48,8 +48,15 @@
 from docutils.io import StringOutput
 from docutils.utils import new_document
 
-from sphinx.builders import Builder
-from sphinx.writers.text import TextWriter
+try:
+    from sphinx.builders import Builder
+except ImportError:
+    from sphinx.builder import Builder
+
+try:
+    from sphinx.writers.text import TextWriter
+except ImportError:
+    from sphinx.textwriter import TextWriter
 
 
 class PydocTopicsBuilder(Builder):