diff --git a/jbpm-document/src/main/java/org/jbpm/document/audit/DocumentCollectionVariableIndexer.java b/jbpm-document/src/main/java/org/jbpm/document/audit/DocumentCollectionVariableIndexer.java
index 0d7c46a9b3..9030a7042a 100644
--- a/jbpm-document/src/main/java/org/jbpm/document/audit/DocumentCollectionVariableIndexer.java
+++ b/jbpm-document/src/main/java/org/jbpm/document/audit/DocumentCollectionVariableIndexer.java
@@ -28,7 +28,7 @@
 
 public class DocumentCollectionVariableIndexer implements ProcessVariableIndexer {
 
-    private static final String PATTERN = "{0} ({1}/{2})";
+    private static final String PATTERN = "{0} ({1}_{2})";
 
     @Override
     public boolean accept(Object variable) {
diff --git a/jbpm-document/src/test/java/org/jbpm/document/audit/DocumentCollectionVariableIndexerTest.java b/jbpm-document/src/test/java/org/jbpm/document/audit/DocumentCollectionVariableIndexerTest.java
index 82575f4b53..1d2901ec27 100644
--- a/jbpm-document/src/test/java/org/jbpm/document/audit/DocumentCollectionVariableIndexerTest.java
+++ b/jbpm-document/src/test/java/org/jbpm/document/audit/DocumentCollectionVariableIndexerTest.java
@@ -76,7 +76,7 @@ public void testIndex() {
 
     private void testDocument(int index, int max, VariableInstanceLog log, DocumentImpl document) {
         Assertions.assertThat(log)
-                .hasFieldOrPropertyWithValue("variableId", VARIABLE_NAME + " (" + (index + 1) + "/" + max + ")")
+                .hasFieldOrPropertyWithValue("variableId", VARIABLE_NAME + " (" + (index + 1) + "_" + max + ")")
                 .hasFieldOrPropertyWithValue("value", document.toString());
     }
 }