diff --git a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/BaseValidator.java b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/BaseValidator.java
index cc8576f70..8016e14bb 100644
--- a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/BaseValidator.java
+++ b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/BaseValidator.java
@@ -53,6 +53,7 @@ POSSIBILITY OF SUCH DAMAGE.
 import java.text.MessageFormat;
 import java.util.List;
 
+import java.util.MissingResourceException;
 import java.util.ResourceBundle;
 import org.apache.commons.lang3.StringUtils;
 import org.hl7.fhir.dstu3.model.Resource;
@@ -150,8 +151,13 @@ public class BaseValidator {
     String message;
     if (theMessageArguments != null && theMessageArguments.length > 0) {
       message = MessageFormat.format(messages.getString(theMessage), theMessageArguments);
-    } else { 
-      message = theMessage;
+    } else {
+      try {
+        message = messages.getString(theMessage);
+      } catch (MissingResourceException e) {
+        // non-internationalized String
+        message = theMessage;
+      }
     }
     return message;
   }
diff --git a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
index 76cb6f88e..493b66b69 100644
--- a/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
+++ b/org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java
@@ -1818,7 +1818,7 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
       warning(errors, IssueType.INVALID, e.line(), e.col(), path, yearIsValid(e.primitiveValue()), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_DATETIME_REASONABLE, e.primitiveValue());
       rule(errors, IssueType.INVALID, e.line(), e.col(), path,
         e.primitiveValue()
-          .matches("([0-9]([0-9]([0-9][1-9]|[1-9]0)|[1-9]00)|[1-9]000)(-(0[1-9]|1[0-2])(-(0[1-9]|[1-2][0-9]|3[0-1])(T([01][0-9]|2[0-3]):[0-5][0-9]:([0-5][0-9]|60)(\\.[0-9]+)?(Z|(\\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?)?)?)?"), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_DATETIME_VALID);
+          .matches("([0-9]([0-9]([0-9][1-9]|[1-9]0)|[1-9]00)|[1-9]000)(-(0[1-9]|1[0-2])(-(0[1-9]|[1-2][0-9]|3[0-1])(T([01][0-9]|2[0-3]):[0-5][0-9]:([0-5][0-9]|60)(\\.[0-9]+)?(Z|(\\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?)?)?)?"), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_DATETIME_VALID, e.primitiveValue());
       rule(errors, IssueType.INVALID, e.line(), e.col(), path, !hasTime(e.primitiveValue()) || hasTimeZone(e.primitiveValue()), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_DATETIME_TZ);
       rule(errors, IssueType.INVALID, e.line(), e.col(), path, !context.hasMaxLength() || context.getMaxLength() == 0 || e.primitiveValue().length() <= context.getMaxLength(), I18nConstants.TYPE_SPECIFIC_CHECKS_DT_PRIMITIVE_LENGTH, context.getMaxLength());
       try {
diff --git a/org.hl7.fhir.validation/src/main/resources/Messages.properties b/org.hl7.fhir.validation/src/main/resources/Messages.properties
index 66b32adce..293880d47 100644
--- a/org.hl7.fhir.validation/src/main/resources/Messages.properties
+++ b/org.hl7.fhir.validation/src/main/resources/Messages.properties
@@ -166,7 +166,6 @@ Terminology_TX_ValueSet_NotFound2 = ValueSet {0} not found by validator
 Type_Specific_Checks_DT_Base64_Valid = The value '{0}' is not a valid Base64 value
 Type_Specific_Checks_DT_Boolean_Value = boolean values must be 'true' or 'false'
 Type_Specific_Checks_DT_Code_WS = The code '{0}' is not valid (whitespace rules)
-Type_Specific_Checks_DT_DateTIme_Valid = Not a valid date time
 Type_Specific_Checks_DT_DateTime_Reasonable = The value '{0}' is outside the range of reasonable years - check for data entry error
 Type_Specific_Checks_DT_DateTime_Regex = The instant '{0}' is not valid (by regex)
 Type_Specific_Checks_DT_DateTime_TZ = if a date has a time, it must have a timezone
diff --git a/org.hl7.fhir.validation/src/main/resources/Messages_de_DE.properties b/org.hl7.fhir.validation/src/main/resources/Messages_de_DE.properties
index 66b32adce..293880d47 100644
--- a/org.hl7.fhir.validation/src/main/resources/Messages_de_DE.properties
+++ b/org.hl7.fhir.validation/src/main/resources/Messages_de_DE.properties
@@ -166,7 +166,6 @@ Terminology_TX_ValueSet_NotFound2 = ValueSet {0} not found by validator
 Type_Specific_Checks_DT_Base64_Valid = The value '{0}' is not a valid Base64 value
 Type_Specific_Checks_DT_Boolean_Value = boolean values must be 'true' or 'false'
 Type_Specific_Checks_DT_Code_WS = The code '{0}' is not valid (whitespace rules)
-Type_Specific_Checks_DT_DateTIme_Valid = Not a valid date time
 Type_Specific_Checks_DT_DateTime_Reasonable = The value '{0}' is outside the range of reasonable years - check for data entry error
 Type_Specific_Checks_DT_DateTime_Regex = The instant '{0}' is not valid (by regex)
 Type_Specific_Checks_DT_DateTime_TZ = if a date has a time, it must have a timezone