--- a/mail/config/mozconfigs/win64/debug
+++ b/mail/config/mozconfigs/win64/debug
@@ -11,8 +11,12 @@ export MOZILLA_OFFICIAL=1
 mk_add_options MOZ_MAKE_FLAGS=-j1
 
 # This is a hack, until we can get a consistent location for both of these.
 if test -e "$topsrcdir/mail/config/mozconfigs/win64/vs2010-mozconfig"; then
   . $topsrcdir/mail/config/mozconfigs/win64/vs2010-mozconfig
 else
   . $topsrcdir/browser/config/mozconfigs/win64/vs2010-mozconfig
 fi
+
+# Run client.py
+mk_add_options CLIENT_PY_ARGS="--hg-options='--verbose --time' --hgtool=../tools/buildfarm/utils/hgtool.py --skip-chatzilla --skip-inspector --skip-venkman --tinderbox-print"
+mk_add_options ALWAYS_RUN_CLIENT_PY=1

--- a/mail/config/mozconfigs/win64/nightly
+++ b/mail/config/mozconfigs/win64/nightly
@@ -12,8 +12,12 @@ export MOZILLA_OFFICIAL=1
 mk_add_options MOZ_MAKE_FLAGS=-j1
 
 # This is a hack, until we can get a consistent location for both of these.
 if test -e "$topsrcdir/mail/config/mozconfigs/win64/vs2010-mozconfig"; then
   . $topsrcdir/mail/config/mozconfigs/win64/vs2010-mozconfig
 else
   . $topsrcdir/browser/config/mozconfigs/win64/vs2010-mozconfig
 fi
+
+# Run client.py
+mk_add_options CLIENT_PY_ARGS="--hg-options='--verbose --time' --hgtool=../tools/buildfarm/utils/hgtool.py --skip-chatzilla --skip-inspector --skip-venkman --tinderbox-print"
+mk_add_options ALWAYS_RUN_CLIENT_PY=1