Index: src/main/java/org/apache/maven/plugin/idea/IdeaProjectMojo.java
===================================================================
--- src/main/java/org/apache/maven/plugin/idea/IdeaProjectMojo.java	(revision 888559)
+++ src/main/java/org/apache/maven/plugin/idea/IdeaProjectMojo.java	(working copy)
@@ -251,6 +251,10 @@
         {
             component.addAttribute( "assert-keyword", "true" );
             component.addAttribute( "jdk-15", "true" );
+            if ( jdkLevel.compareTo( "1.6" ) >= 0 )
+            {
+                component.addAttribute( "languageLevel", "JDK_1_6" );
+            }
         }
         else
         {