diff --git a/debian/changelog b/debian/changelog
index 0f16b5d0a..a2d460f82 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,8 @@
 linux (4.9.18-2) UNRELEASED; urgency=medium
 
   * w1: Really enable W1_MASTER_GPIO as module (Closes: #858975)
+  * debian/rules.real: Undefine $LANGUAGE, which can break debug symbols for
+    vDSOs (Closes: #859807)
 
  -- Ben Hutchings <ben@decadent.org.uk>  Thu, 30 Mar 2017 18:27:30 +0100
 
diff --git a/debian/rules.real b/debian/rules.real
index 000cb3254..21c75b7e3 100644
--- a/debian/rules.real
+++ b/debian/rules.real
@@ -31,6 +31,7 @@ export DH_OPTIONS
 export DEB_HOST_ARCH DEB_HOST_GNU_TYPE DEB_BUILD_ARCH
 export DEB_BUILD_PATH = $(CURDIR)  # for dpkg-buildflags
 export LC_ALL = C.UTF-8
+undefine LANGUAGE
 
 include debian/rules.defs