Build setup tweak to work around release plugin bug.

http://jira.codehaus.org/browse/MRELEASE-812
(cherry picked from commit c863881)

pom.xml

@@ -136,19 +136,26 @@
           <artifactId>maven-javadoc-plugin</artifactId>
           <version>2.9</version>
         </plugin>
-
-        <plugin>
-          <groupId>org.apache.maven.plugins</groupId>
-          <artifactId>maven-release-plugin</artifactId>
-          <version>2.3.2</version>
-          <configuration>
-            <autoVersionSubmodules>true</autoVersionSubmodules>
-          </configuration>
-        </plugin>
       </plugins>
     </pluginManagement>
 
     <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-release-plugin</artifactId>
+        <version>2.4.2</version>
+        <dependencies>
+          <dependency>
+            <groupId>org.apache.maven.scm</groupId>
+            <artifactId>maven-scm-provider-gitexe</artifactId>
+            <version>1.9</version>
+          </dependency>
+        </dependencies>
+        <configuration>
+          <autoVersionSubmodules>true</autoVersionSubmodules>
+        </configuration>
+      </plugin>
+
       <plugin>
         <groupId>org.apache.maven.plugins</groupId>
         <artifactId>maven-checkstyle-plugin</artifactId>