diff --git a/build.properties b/build.properties
index defe62eb22..0cca0f9001 100644
--- a/build.properties
+++ b/build.properties
@@ -16,7 +16,7 @@
 # under the License.
 
 classworlds.version=1.2-alpha-7
-plexus.version=1.0-alpha-19
+plexus.version=1.0-alpha-20
 plexus-archiver.version=1.0-alpha-8
 plexus-utils.version=1.4.1
 plexus-interactivity-api.version=1.0-alpha-6-SNAPSHOT
diff --git a/pom.xml b/pom.xml
index 3f11a4bc18..eb5180b9ce 100644
--- a/pom.xml
+++ b/pom.xml
@@ -136,7 +136,7 @@ under the License.
     <module>maven-embedder</module>
   </modules>
   <properties>
-    <plexusVersion>1.0-alpha-19</plexusVersion>
+    <plexusVersion>1.0-alpha-20</plexusVersion>
     <wagonVersion>1.0-beta-2</wagonVersion>
   </properties>
   <dependencies>