Removed checksum-maven-plugin in favour of a simple bash script which signs everything.
diff --git a/pom.xml b/pom.xml
index a0dea0c..7b77621 100644
--- a/pom.xml
+++ b/pom.xml
@@ -229,24 +229,6 @@
                     </execution>
                 </executions>
             </plugin>
-            <plugin>
-                <groupId>net.nicoulaj.maven.plugins</groupId>
-                <artifactId>checksum-maven-plugin</artifactId>
-                <version>1.8</version>
-                <executions>
-                    <execution>
-                        <goals>
-                            <goal>artifacts</goal>
-                        </goals>
-                    </execution>
-                </executions>
-                <configuration>
-                    <algorithms>
-                        <algorithm>SHA-512</algorithm>
-                    </algorithms>
-                    <attachChecksums>true</attachChecksums>
-                </configuration>
-            </plugin>
         </plugins>
         <pluginManagement>
             <plugins>
diff --git a/sign.sh b/sign.sh
new file mode 100755
index 0000000..0a8bf6f
--- /dev/null
+++ b/sign.sh
@@ -0,0 +1,11 @@
+#!/bin/bash
+
+# Change to the Maven repository
+cd ~/.m2/repository/org/apache/samoa
+
+for filename in $(find . -not -name '*.sha512' -and -not -name '*.asc' -and -not -name '*_remote.repositories'); do
+	if [ ! -f $filename.sha512 ] && [ ! -d $filename ]; then
+		echo $filename
+		gpg --print-md SHA512 $filename > $filename.sha512
+	fi
+done