diff --git a/WHATSNEW b/WHATSNEW
index 566586809..f82e28fb5 100644
--- a/WHATSNEW
+++ b/WHATSNEW
@@ -123,7 +123,11 @@ Fixed bugs:
    fields rather than UTF-8 filenames and the EFS-Flag.
 
  * Access to DirectoryScanner's default excludes wasn't synchronized.
-   BigZilla Report 52188.
+   Bugzilla Report 52188.
+
+ * When a Project instance was created by a custom tasks its
+   createTask method didn't work.
+   Bugzilla Report 50788.
 
 Other changes:
 --------------
diff --git a/src/main/org/apache/tools/ant/ComponentHelper.java b/src/main/org/apache/tools/ant/ComponentHelper.java
index 368a3b125..ad32faf63 100644
--- a/src/main/org/apache/tools/ant/ComponentHelper.java
+++ b/src/main/org/apache/tools/ant/ComponentHelper.java
@@ -855,6 +855,14 @@ public class ComponentHelper  {
             return; // Already processed
         }
         checkedNamespaces.add(uri);
+
+        if (antTypeTable.size() == 0) {
+            // Project instance doesn't know the tasks and types
+            // defined in defaults.properties, likely created by the
+            // user - without those definitions it cannot parse antlib
+            // files as taskdef, typedef and friends are unknown
+            initDefaultDefinitions();
+        }
         Typedef definer = new Typedef();
         definer.setProject(project);
         definer.init();
diff --git a/src/tests/antunit/core/createtask-test.xml b/src/tests/antunit/core/createtask-test.xml
new file mode 100644
index 000000000..b69633b30
--- /dev/null
+++ b/src/tests/antunit/core/createtask-test.xml
@@ -0,0 +1,50 @@
+<?xml version="1.0"?>
+<!--
+  Licensed to the Apache Software Foundation (ASF) under one or more
+  contributor license agreements.  See the NOTICE file distributed with
+  this work for additional information regarding copyright ownership.
+  The ASF licenses this file to You under the Apache License, Version 2.0
+  (the "License"); you may not use this file except in compliance with
+  the License.  You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<project xmlns:au="antlib:org.apache.ant.antunit" default="antunit">
+
+  <import file="../antunit-base.xml"/>
+
+  <target name="setUp">
+    <mkdir dir="${input}"/>
+    <mkdir dir="${output}"/>
+  </target>
+
+  <target name="-create-task" depends="setUp">
+    <mkdir dir="${input}/org/apache/ant/example"/>
+    <echo file="${input}/org/apache/ant/example/Foo.java"><![CDATA[
+package org.apache.ant.example;
+import org.apache.tools.ant.Project;
+import org.apache.tools.ant.Task;
+public class Foo extends Task {
+    public void execute() {
+        new Project().createTask("Delete");
+    }
+}
+]]></echo>
+    <javac srcdir="${input}" destdir="${output}"/>
+    <taskdef name="foo" classname="org.apache.ant.example.Foo">
+      <classpath location="${output}"/>
+    </taskdef>
+  </target>
+
+  <target name="testCreateTaskInFreshProject"
+          description="https://issues.apache.org/bugzilla/show_bug.cgi?id=50788"
+          depends="-create-task">
+    <foo/>
+  </target>
+</project>