diff --git a/src/dzitilesource.js b/src/dzitilesource.js
index 9410ee68..1bdfa9cf 100644
--- a/src/dzitilesource.js
+++ b/src/dzitilesource.js
@@ -31,7 +31,6 @@
  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-/* global processDZIError:true */
 
 (function( $ ){
 
@@ -284,7 +283,7 @@ function configureFromXML( tileSource, xmlDoc ){
     } else if ( rootName == "Collection" ) {
         throw new Error( $.getString( "Errors.Dzc" ) );
     } else if ( rootName == "Error" ) {
-        return processDZIError( root );
+        return $._processDZIError( root );
     }
 
     throw new Error( $.getString( "Errors.Dzi" ) );
diff --git a/src/openseadragon.js b/src/openseadragon.js
index 4f0e5bce..0bd32ba5 100644
--- a/src/openseadragon.js
+++ b/src/openseadragon.js
@@ -1934,5 +1934,7 @@ window.OpenSeadragon = window.OpenSeadragon || function( options ){
 
         throw new Error(message);
     }
+    // Add an alias so this is in-scope for dzitilesource but obviously not a blessed public method:
+    $._processDZIError = processDZIError;
 
 }( OpenSeadragon ));