diff --git a/core/src/main/java/org/jclouds/util/DateService.java b/core/src/main/java/org/jclouds/util/DateService.java
index 0b4cfcddd2..51bcf11da6 100644
--- a/core/src/main/java/org/jclouds/util/DateService.java
+++ b/core/src/main/java/org/jclouds/util/DateService.java
@@ -94,7 +94,7 @@ public class DateService {
          try {
             return new DateTime(rfc822SimpleDateFormat.parse(toParse));
          } catch (ParseException e) {
-            return null;
+            throw new RuntimeException(e);
          }
       }
    }
@@ -116,7 +116,7 @@ public class DateService {
          try {
             return new DateTime(iso8601SimpleDateFormat.parse(toParse));
          } catch (ParseException e) {
-            return null;
+            throw new RuntimeException(e);
          }
       }
    }