diff --git a/jformatstring.changes b/jformatstring.changes
index bec6043..4c37c5b 100644
--- a/jformatstring.changes
+++ b/jformatstring.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Wed Jan 10 04:09:03 UTC 2018 - bwiedemann@suse.com
+
+- Generate javadoc without timestamp to make build reproducible (boo#1047218)
+
 -------------------------------------------------------------------
 Fri Dec 22 12:24:36 UTC 2017 - fstrba@suse.com
 
diff --git a/jformatstring.spec b/jformatstring.spec
index 695e9f9..b6bec47 100644
--- a/jformatstring.spec
+++ b/jformatstring.spec
@@ -72,7 +72,7 @@ build-jar-repository -s -p lib junit
 export CLASSPATH=
 export OPT_JAR_LIST=:
 ant -Dant.build.javac.source=1.6 -Dant.build.javac.target=1.6
-javadoc -d javadoc -source 1.6 \
+javadoc -notimestamp -d javadoc -source 1.6 \
            -sourcepath src/java \
            -classpath build/classes:$(build-classpath junit) \
            edu.umd.cs.findbugs.formatStringChecker