diff --git a/solenv/gbuild/Jar.mk b/solenv/gbuild/Jar.mk
index 17dfd3dfa09c..9e9c83f4c4c7 100644
--- a/solenv/gbuild/Jar.mk
+++ b/solenv/gbuild/Jar.mk
@@ -217,8 +217,9 @@ $$(call gb_Output_error,\
  gb_Jar_add_jar: use gb_Jar_use_jar instead.)
 endef
 
-# URE jars are not added to manifest classpath
-gb_Jar_default_jars := $(gb_Jar_URE)
+# URE jars are not added to manifest classpath; and neither is unoil.jar, which
+# is available at runtime via URE_MORE_JAVA_TYPES:
+gb_Jar_default_jars := $(gb_Jar_URE) unoil
 
 # remember: classpath is "inherited" to ClassSet
 define gb_Jar_use_jar