diff --git a/drools-compiler/src/test/java/org/drools/compiler/integrationtests/ExpirationTest.java b/drools-compiler/src/test/java/org/drools/compiler/integrationtests/ExpirationTest.java
index 6946bbb62a7..87a728a6a88 100644
--- a/drools-compiler/src/test/java/org/drools/compiler/integrationtests/ExpirationTest.java
+++ b/drools-compiler/src/test/java/org/drools/compiler/integrationtests/ExpirationTest.java
@@ -637,4 +637,46 @@ public String toString() {
             return "DummyEvent{" + "id=" + id + ", eventTimestamp=" + eventTimestamp + ", state=" + state + '}';
         }
     }
+
+    @Test
+    public void testEventSameContraint() throws InterruptedException {
+        // DROOLS-4580
+        final String drl =
+                " package org.drools.compiler.integrationtests;\n" +
+                " import " + DummyEvent.class.getCanonicalName() + ";\n" +
+                " declare DummyEvent\n" +
+                "     @role( event )\n" +
+                "     @timestamp( eventTimestamp )\n" +
+                " end\n" +
+                " \n" +
+                " rule R1 when\n" +
+                "     $dummyEvent : DummyEvent(state != \"release\")\n" +
+                "     $otherDummyEvent : DummyEvent(this != $dummyEvent, this before $dummyEvent, idA == $dummyEvent.idA)\n" +
+                " then \n" +
+                "     System.out.println(\"R1\");\n" +
+                " end\n" +
+                " rule R2 when\n" +
+                "     $dummyEvent : DummyEvent(state != \"release\")\n" +
+                "     $otherDummyEvent : DummyEvent(this != $dummyEvent, this before $dummyEvent, idA == $dummyEvent.idA)\n" +
+                " then \n" +
+                "     System.out.println(\"R2\");\n" +
+                " end\n";
+
+        final KieSessionConfiguration sessionConfig = KnowledgeBaseFactory.newKnowledgeSessionConfiguration();
+        sessionConfig.setOption( ClockTypeOption.get( ClockType.PSEUDO_CLOCK.getId() ) );
+
+        final KieHelper helper = new KieHelper();
+        helper.addContent( drl, ResourceType.DRL );
+        final KieBase kieBase = helper.build( EventProcessingOption.STREAM );
+        final KieSession kieSession = kieBase.newKieSession( sessionConfig, null );
+
+        PseudoClockScheduler clock = kieSession.getSessionClock();
+        final long currentTime = System.currentTimeMillis();
+        clock.setStartupTime(currentTime - 1);
+
+        kieSession.insert(new DummyEvent(1, currentTime));
+        kieSession.insert(new DummyEvent(2, currentTime - Duration.ofHours(8).toMillis()));
+
+        Assertions.assertThat(kieSession.fireAllRules()).isEqualTo(2);
+    }
 }
diff --git a/drools-core/src/main/java/org/drools/core/reteoo/builder/BuildUtils.java b/drools-core/src/main/java/org/drools/core/reteoo/builder/BuildUtils.java
index d548a521f55..1e47339ea23 100755
--- a/drools-core/src/main/java/org/drools/core/reteoo/builder/BuildUtils.java
+++ b/drools-core/src/main/java/org/drools/core/reteoo/builder/BuildUtils.java
@@ -173,8 +173,9 @@ private void mergeNodes(BaseNode node, BaseNode duplicate) {
             int i = 0;
             for (BetaNodeFieldConstraint betaConstraint : betaConstraints) {
                 if (betaConstraint instanceof MvelConstraint) {
-                    ((MvelConstraint) betaConstraint).addPackageNames(((MvelConstraint) ((BetaNode) duplicate).getConstraints()[i++]).getPackageNames());
+                    ((MvelConstraint) betaConstraint).addPackageNames(((MvelConstraint) ((BetaNode) duplicate).getConstraints()[i]).getPackageNames());
                 }
+                i++;
             }
         }
     }