document new PYTHONWARNINGS env var
diff --git a/Misc/python.man b/Misc/python.man
index d981fba..261a118 100644
--- a/Misc/python.man
+++ b/Misc/python.man
@@ -411,6 +411,9 @@
If this is set to a non-empty string it is equivalent to specifying
the \fB\-v\fP option. If set to an integer, it is equivalent to
specifying \fB\-v\fP multiple times.
+.IP PYTHONWARNINGS
+If this is set to a comma-separated string it is equivalent to
+specifying the \fB\-W\fP option for each separate value.
.SH AUTHOR
The Python Software Foundation: http://www.python.org/psf
.SH INTERNET RESOURCES