diff --git a/build.xml b/build.xml
index 4ea048e59a..b2ed09d96d 100644
--- a/build.xml
+++ b/build.xml
@@ -517,6 +517,7 @@ under the License.
         <path refid="ooxml.classpath"/>
         <path refid="ooxml.xmlsec.classpath"/>
         <path refid="test.jar.classpath"/>
+        <pathelement location="${main.slf4j-api.jar}"/>
         <path path="${env.CLASSPATH}"/>
     </path>