Fix some issues found by Jacques Ducasse on the docs list.
diff --git a/Doc/library/pdb.rst b/Doc/library/pdb.rst
index cd1597f..f6651ab 100644
--- a/Doc/library/pdb.rst
+++ b/Doc/library/pdb.rst
@@ -22,7 +22,7 @@
The debugger is extensible --- it is actually defined as the class :class:`Pdb`.
This is currently undocumented but easily understood by reading the source. The
-extension interface uses the modules :mod:`bdb` (undocumented) and :mod:`cmd`.
+extension interface uses the modules :mod:`bdb` and :mod:`cmd`.
The debugger's prompt is ``(Pdb)``. Typical usage to run a program under control
of the debugger is::