diff --git a/java-1.8.0-openjdk.spec b/java-1.8.0-openjdk.spec
index ff8954e..5278556 100644
--- a/java-1.8.0-openjdk.spec
+++ b/java-1.8.0-openjdk.spec
@@ -791,7 +791,7 @@ exit 0
 # FIXME: identical binaries are copied, not linked. This needs to be
 # fixed upstream.
 %post headless
-ext=.gz
+ext=.xz
 alternatives \
   --install %{_bindir}/java java %{jrebindir}/java %{priority} \
   --slave %{_jvmdir}/jre jre %{_jvmdir}/%{jrelnk} \
@@ -853,7 +853,7 @@ then
 fi
 
 %post devel
-ext=.gz
+ext=.xz
 alternatives \
   --install %{_bindir}/javac javac %{sdkbindir}/javac %{priority} \
   --slave %{_jvmdir}/java java_sdk %{_jvmdir}/%{sdklnk} \