Index: src/java/org/apache/ivy/core/settings/XmlSettingsParser.java
===================================================================
--- src/java/org/apache/ivy/core/settings/XmlSettingsParser.java	(revision 1415344)
+++ src/java/org/apache/ivy/core/settings/XmlSettingsParser.java	(working copy)
@@ -422,6 +422,10 @@
                         ivy.setSettingsVariables(
                             Checks.checkAbsolute(settingsFile, 
                             "settings include path"));
+                        boolean optional = Boolean.parseBoolean((String) attributes.get("optional"));
+                        if (optional && !settingsFile.exists()) {
+                            return;
+                        }
                     } catch (URISyntaxException e) {
                         // try to make the best of it...
                         ivy.setSettingsVariables(