diff --git a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDao.java b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDao.java
index 19b1ff91f09..e117fe997ff 100644
--- a/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDao.java
+++ b/hapi-fhir-jpaserver-base/src/main/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDao.java
@@ -524,8 +524,8 @@ public abstract class BaseHapiFhirDao<T extends IBaseResource> extends BaseStora
 				.map(Throwable::getMessage)
 				.collect(Collectors.joining(", "));
 			throw new InternalErrorException(
-				Msg.code(2019) +
-					"Tag get/create failed after "
+				Msg.code(2023)
+					+ "Tag get/create failed after "
 					+ TOTAL_TAG_READ_ATTEMPTS
 					+ " attempts with error(s): "
 					+ msg
diff --git a/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDaoTest.java b/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDaoTest.java
index dae163faab6..7d680fc7ab7 100644
--- a/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDaoTest.java
+++ b/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/BaseHapiFhirDaoTest.java
@@ -15,7 +15,6 @@ import org.jetbrains.annotations.Nullable;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
@@ -149,7 +148,6 @@ public class BaseHapiFhirDaoTest {
 		return from;
 	}
 
-	@Disabled
 	@Test
 	public void getTagOrNull_raceCondition_wontUpsertDuplicates() throws InterruptedException, ExecutionException {
 		/*
@@ -179,7 +177,6 @@ public class BaseHapiFhirDaoTest {
 		String scheme = "http://localhost";
 		String term = "code123";
 		String label = "hollow world";
-		TransactionDetails transactionDetails = new TransactionDetails();
 		String raceConditionError = "Entity exists; if this is logged, you have race condition issues!";
 
 		TagDefinition tagDefinition = new TagDefinition(tagType,
@@ -275,7 +272,7 @@ public class BaseHapiFhirDaoTest {
 		Runnable task = () -> {
 			latch.countDown();
 			try {
-				TagDefinition retTag = myTestDao.getTagOrNull(transactionDetails, tagType, scheme, term, label);
+				TagDefinition retTag = myTestDao.getTagOrNull(new TransactionDetails(), tagType, scheme, term, label);
 				outcomes.put(retTag.hashCode(), retTag);
 				counter.incrementAndGet();
 			} catch (Exception ex) {
@@ -367,7 +364,7 @@ public class BaseHapiFhirDaoTest {
 			fail();
 		} catch (Exception ex) {
 			// verify
-			assertEquals("HAPI-2019: Tag get/create failed after 10 attempts with error(s): " + exMsg, ex.getMessage());
+			assertTrue(ex.getMessage().contains("Tag get/create failed after 10 attempts with error(s): " + exMsg));
 
 			ArgumentCaptor<ILoggingEvent> appenderCaptor = ArgumentCaptor.forClass(ILoggingEvent.class);
 			verify(myAppender, Mockito.times(10))
diff --git a/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/r4/FhirResourceDaoR4CreateTest.java b/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/r4/FhirResourceDaoR4CreateTest.java
index 36cb6ad26dd..b44f9cf4f66 100644
--- a/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/r4/FhirResourceDaoR4CreateTest.java
+++ b/hapi-fhir-jpaserver-base/src/test/java/ca/uhn/fhir/jpa/dao/r4/FhirResourceDaoR4CreateTest.java
@@ -3,6 +3,7 @@ package ca.uhn.fhir.jpa.dao.r4;
 import ca.uhn.fhir.i18n.Msg;
 import ca.uhn.fhir.jpa.api.config.DaoConfig;
 import ca.uhn.fhir.jpa.api.model.DaoMethodOutcome;
+import ca.uhn.fhir.jpa.config.TestR4Config;
 import ca.uhn.fhir.jpa.model.entity.ModelConfig;
 import ca.uhn.fhir.jpa.model.entity.NormalizedQuantitySearchLevel;
 import ca.uhn.fhir.jpa.model.entity.ResourceHistoryTable;
@@ -60,7 +61,10 @@ import java.util.concurrent.Future;
 import java.util.stream.Collectors;
 
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.*;
+import static org.hamcrest.Matchers.contains;
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.empty;
+import static org.hamcrest.Matchers.matchesPattern;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
@@ -1009,8 +1013,10 @@ public class FhirResourceDaoR4CreateTest extends BaseJpaR4Test {
 
 	@Test
 	public void testResourceWithTagCreationNoFailures() throws ExecutionException, InterruptedException {
-		// this was 5, but our random connection pool runs as small as 3, and this solution needs a spare connection to be safe.
-		ExecutorService pool = Executors.newFixedThreadPool(2);
+		// we need to leave at least one free thread
+		// due to a REQUIRED_NEW transaction internally
+		int maxThreadsUsed = TestR4Config.ourMaxThreads - 1;
+		ExecutorService pool = Executors.newFixedThreadPool(Math.min(maxThreadsUsed, 5));
 		try {
 			Coding tag = new Coding();
 			tag.setCode("code123");
@@ -1035,7 +1041,9 @@ public class FhirResourceDaoR4CreateTest extends BaseJpaR4Test {
 						try {
 							myPatientDao.update(updatePatient);
 						} catch (ResourceVersionConflictException e) {
-							assertThat(e.getMessage(), startsWith(Msg.code(550) + Msg.code(823)));
+							assertTrue(e.getMessage().contains(
+								"The operation has failed with a version constraint failure. This generally means that two clients/threads were trying to update the same resource at the same time, and this request was chosen as the failing request."
+							));
 						}
 					} catch (Exception e) {
 						ourLog.error("Failure", e);