diff --git a/cglib.changes b/cglib.changes
index 765d0df..5dc47ed 100644
--- a/cglib.changes
+++ b/cglib.changes
@@ -1,3 +1,11 @@
+-------------------------------------------------------------------
+Mon Sep 18 06:30:45 UTC 2017 - fstrba@suse.com
+
+- Specify java source and target 1.6 in order to allow building
+  with jdk9
+- Fix javadoc generation
+- Clean spec file
+
 -------------------------------------------------------------------
 Fri May 19 08:51:39 UTC 2017 - mpluskal@suse.com
 
diff --git a/cglib.spec b/cglib.spec
index ecc2802..c0922c1 100644
--- a/cglib.spec
+++ b/cglib.spec
@@ -28,7 +28,7 @@ Source1:        /%{name}-%{version}.pom
 # Remove the repackaging step that includes other jars into the final thing
 Patch0:         %{name}-build_xml.patch
 BuildRequires:  ant >= 1.6
-BuildRequires:  java-devel
+BuildRequires:  fdupes
 BuildRequires:  java-devel >= 1.6.0
 # Needed for maven conversions
 BuildRequires:  javapackages-local
@@ -57,11 +57,13 @@ runtime.
 %setup -q -T -c -n %{name}
 unzip -q %{SOURCE0}
 rm lib/*.jar
+build-jar-repository -s -p lib objectweb-asm ant
 %patch0 -p1
 
 %build
-export CLASSPATH=`build-classpath objectweb-asm`
-ant jar javadoc
+ant \
+    -Dcompile.target=1.6 -Dcompile.source=1.6 \
+    jar javadoc
 
 %install
 # jars
@@ -71,6 +73,7 @@ cp -p dist/%{name}-%{version}.jar %{buildroot}%{_javadir}/%{name}.jar
 # javadoc
 mkdir -p %{buildroot}%{_javadocdir}/
 cp -r docs %{buildroot}%{_javadocdir}/%{name}
+%fdupes -s %{buildroot}%{_javadocdir}/%{name}
 
 #maven pom
 mkdir -p %{buildroot}%{_mavenpomdir}
@@ -78,14 +81,12 @@ cp %{SOURCE1} %{buildroot}%{_mavenpomdir}/JPP-%{name}.pom
 %add_maven_depmap JPP-%{name}.pom %{name}.jar
 
 %files
-%defattr(-,root,root,-)
 %doc LICENSE NOTICE
 %{_javadir}/*.jar
 %{_mavenpomdir}/*
 %config(noreplace) %{_datadir}/maven-metadata/%{name}.xml
 
 %files javadoc
-%defattr(-,root,root,-)
 %{_javadocdir}/%{name}
 
 %changelog