diff --git a/drydocker/copenhagen/test_unit.sh b/drydocker/copenhagen/test_unit.sh
index bd65a3e..fea7fb6 100755
--- a/drydocker/copenhagen/test_unit.sh
+++ b/drydocker/copenhagen/test_unit.sh
@@ -1,16 +1,16 @@
 #!/bin/bash
 
 pushd /srv/${PACKAGE}.git
 
 pushd tests
 phpunit \
-    --include-path /usr/share/roundcubemail/program/lib/ \
+    --include-path /usr/share/roundcubemail/program/lib/:/usr/share/roundcubemail/plugins/libkolab/lib/ \
     --debug ; retval=$?
 
 if [ ${retval} -ne 0 ]; then
     echo "FAILED unit tests."
     exit 1
 fi
 
 popd
 popd