diff --git a/src/main/org/apache/tools/ant/taskdefs/defaults.properties b/src/main/org/apache/tools/ant/taskdefs/defaults.properties
index 84b41089d..8c0d4b7cf 100644
--- a/src/main/org/apache/tools/ant/taskdefs/defaults.properties
+++ b/src/main/org/apache/tools/ant/taskdefs/defaults.properties
@@ -202,6 +202,7 @@ jsharpc=org.apache.tools.ant.taskdefs.optional.dotnet.JSharp
 rexec=org.apache.tools.ant.taskdefs.optional.net.RExecTask
 scriptdef=org.apache.tools.ant.taskdefs.optional.script.ScriptDef
 ildasm=org.apache.tools.ant.taskdefs.optional.dotnet.Ildasm
+apt=org.apache.tools.ant.taskdefs.Apt
 
 # deprecated ant tasks (kept for back compatibility)
 starteam=org.apache.tools.ant.taskdefs.optional.scm.AntStarTeamCheckOut