bump project version to 4.0.0-SNAPSHOT

Signed-off-by: Lukas Jungmann <lukas.jungmann@oracle.com>
diff --git a/jaxb-api-test/pom.xml b/jaxb-api-test/pom.xml
index b088880..666d4f4 100644
--- a/jaxb-api-test/pom.xml
+++ b/jaxb-api-test/pom.xml
@@ -15,7 +15,7 @@
     <parent>
         <artifactId>jakarta.xml.bind-api-parent</artifactId>
         <groupId>jakarta.xml.bind</groupId>
-        <version>3.0.2-SNAPSHOT</version>
+        <version>4.0.0-SNAPSHOT</version>
     </parent>
     <modelVersion>4.0.0</modelVersion>
 
diff --git a/jaxb-api/pom.xml b/jaxb-api/pom.xml
index a318a9d..f8341f3 100644
--- a/jaxb-api/pom.xml
+++ b/jaxb-api/pom.xml
@@ -15,7 +15,7 @@
     <parent>
         <artifactId>jakarta.xml.bind-api-parent</artifactId>
         <groupId>jakarta.xml.bind</groupId>
-        <version>3.0.2-SNAPSHOT</version>
+        <version>4.0.0-SNAPSHOT</version>
         <relativePath>../pom.xml</relativePath>
     </parent>
     <modelVersion>4.0.0</modelVersion>
diff --git a/pom.xml b/pom.xml
index 6329614..f84ce68 100644
--- a/pom.xml
+++ b/pom.xml
@@ -24,7 +24,7 @@
 
     <groupId>jakarta.xml.bind</groupId>
     <artifactId>jakarta.xml.bind-api-parent</artifactId>
-    <version>3.0.2-SNAPSHOT</version>
+    <version>4.0.0-SNAPSHOT</version>
     <packaging>pom</packaging>
     <name>Jakarta XML Binding</name>
     <description>Jakarta XML Binding API</description>
@@ -83,7 +83,7 @@
         <release.spec.date>Jul 2017</release.spec.date>
         <api.package>jakarta.xml.bind</api.package>
         <extension.name>jakarta.xml.bind</extension.name>
-        <spec.version>3.0</spec.version>
+        <spec.version>4.0</spec.version>
         <impl.version>0</impl.version>
         <activation.version>2.0.1</activation.version>
         <config.dir>${project.basedir}/etc/config</config.dir>
diff --git a/spec/pom.xml b/spec/pom.xml
index 339eb19..aca650a 100644
--- a/spec/pom.xml
+++ b/spec/pom.xml
@@ -28,7 +28,7 @@
     <groupId>jakarta.xml.bind</groupId>
     <artifactId>xml-binding-spec</artifactId>
     <packaging>pom</packaging>
-    <version>3.0</version>
+    <version>4.0-SNAPSHOT</version>
     <name>Jakarta XML Binding Specification</name>
 
     <properties>