diff --git a/elements/pypi/README.rst b/elements/pypi/README.rst
index 468972a5a..e0dfc17f8 100644
--- a/elements/pypi/README.rst
+++ b/elements/pypi/README.rst
@@ -16,18 +16,18 @@ To disable the pypi.python.org index without using --offline (e.g. when working
 behind a corporate firewall that prohibits pypi.python.org) set
 DIB\_NO\_PYPI\_PIP to any non-empty value.
 
-To use an arbitrary mirror set PYPI\_MIRROR\_URL=http[s]://somevalue/
+To use an arbitrary mirror set DIB\_PYPI\_MIRROR\_URL=http[s]://somevalue/
 
-Additional mirrors can be added by exporting PYPI\_MIRROR\_URL\_1=... etc. Only
-the one mirror can be used by easy-install, but since wheels need to be in the
-first mirror to be used, the last listed mirror is used as the pydistutils
-index. NB: The sort order for these variables is a simple string sort - if
-you have more than 9 additional mirrors, some care will be needed.
+Additional mirrors can be added by exporting DIB\_PYPI\_MIRROR\_URL\_1=... etc.
+Only the one mirror can be used by easy-install, but since wheels need to be in
+the first mirror to be used, the last listed mirror is used as the pydistutils
+index. NB: The sort order for these variables is a simple string sort - if you
+have more than 9 additional mirrors, some care will be needed.
 
 A typical use of this element is thus:
-export PYPI\_MIRROR\_URL=http://site/pypi/Ubuntu-13.10
-export PYPI\_MIRROR\_URL\_1=http://site/pypi/
-export PYPI\_MIRROR\_URL\_2=file:///tmp/pypi
+export DIB\_PYPI\_MIRROR\_URL=http://site/pypi/Ubuntu-13.10
+export DIB\_PYPI\_MIRROR\_URL\_1=http://site/pypi/
+export DIB\_PYPI\_MIRROR\_URL\_2=file:///tmp/pypi
 
 [devpi-server](https://git.openstack.org/cgit/openstack-infra/pypi-mirro://pypi.python.org/pypi/devpi-server)
 can be useful in making a partial PyPI mirror suitable for building images. For
@@ -41,9 +41,9 @@ instance:
 
 * Re-export your variables to point at the new mirror:
 
-    export PYPI\_MIRROR\_URL=http://machinename:3141/
-    unset PYPI\__MIRROR\_URL\_1
-    unset PYPI\__MIRROR\_URL\_1
+    export DIB\_PYPI\_MIRROR\_URL=http://machinename:3141/
+    unset DIB\_PYPI\__MIRROR\_URL\_1
+    unset DIB\_PYPI\__MIRROR\_URL\_2
 
 The next time packages are installed, they'll be cached on the local devpi
 server; subsequent runs pointed at the same mirror will use the local cache if
diff --git a/elements/pypi/pre-install.d/00-configure-pypi-mirror b/elements/pypi/pre-install.d/00-configure-pypi-mirror
index 1a217b7cb..c1d3b55bc 100755
--- a/elements/pypi/pre-install.d/00-configure-pypi-mirror
+++ b/elements/pypi/pre-install.d/00-configure-pypi-mirror
@@ -21,8 +21,16 @@ def main():
     home = os.path.expanduser("~")
     backup_configs(home)
     indices = []
-    if os.environ.get('PYPI_MIRROR_URL'):
-        candidates = [k for k in os.environ if k.startswith('PYPI_MIRROR_URL')]
+    if (os.environ.get('DIB_PYPI_MIRROR_URL') or
+            os.environ.get('PYPI_MIRROR_URL')):
+        candidates = [k for k in os.environ if
+                      k.startswith('DIB_PYPI_MIRROR_URL')]
+        back_compat = [k for k in os.environ if
+                       k.startswith('PYPI_MIRROR_URL')]
+        if len(back_compat) > 0:
+            print('DEPRECATION WARNING: Please use DIB_PYPI_MIRROR_URL* rather'
+                  ' than PYPI_MIRROR_URL*')
+        candidates += back_compat
         indices = list(map(os.environ.get, sorted(candidates)))
     else:
         indices = ['file:///tmp/pypi']