diff --git a/src/main/java/org/apache/maven/shared/archiver/ManifestConfiguration.java b/src/main/java/org/apache/maven/shared/archiver/ManifestConfiguration.java
index 8e2c056..6198b1c 100644
--- a/src/main/java/org/apache/maven/shared/archiver/ManifestConfiguration.java
+++ b/src/main/java/org/apache/maven/shared/archiver/ManifestConfiguration.java
@@ -218,7 +218,7 @@ public void setAddExtensions(boolean addExtensions) {
      * @param classpathPrefix the prefix
      */
     public void setClasspathPrefix(String classpathPrefix) {
-        this.classpathPrefix = classpathPrefix;
+        this.classpathPrefix = classpathPrefix != null ? classpathPrefix : "";
     }
 
     /**
diff --git a/src/test/java/org/apache/maven/shared/archiver/ManifestConfigurationTest.java b/src/test/java/org/apache/maven/shared/archiver/ManifestConfigurationTest.java
index a0d74e0..e36c71c 100644
--- a/src/test/java/org/apache/maven/shared/archiver/ManifestConfigurationTest.java
+++ b/src/test/java/org/apache/maven/shared/archiver/ManifestConfigurationTest.java
@@ -55,4 +55,10 @@ void getClasspathPrefixShouldReturnTheTrailingSlash() {
         manifestConfiguration.setClasspathPrefix("const/");
         assertThat(manifestConfiguration.getClasspathPrefix()).isEqualTo("const/");
     }
+
+    @Test
+    void getClasspathPrefixShouldHandleNull() {
+        manifestConfiguration.setClasspathPrefix(null);
+        assertThat(manifestConfiguration.getClasspathPrefix()).isEmpty();
+    }
 }