Index: model/org/eclipse/jdt/internal/core/util/Util.java
===================================================================
RCS file: /home/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/util/Util.java,v
retrieving revision 1.81
diff -u -r1.81 Util.java
--- model/org/eclipse/jdt/internal/core/util/Util.java	7 Dec 2005 11:27:15 -0000	1.81
+++ model/org/eclipse/jdt/internal/core/util/Util.java	21 Dec 2005 16:57:18 -0000
@@ -750,7 +750,19 @@
 				JAVA_LIKE_EXTENSIONS = new char[][] {SuffixConstants.EXTENSION_java.toCharArray()};
 			else {
 				IContentType javaContentType = Platform.getContentTypeManager().getContentType(JavaCore.JAVA_SOURCE_CONTENT_TYPE);
-				String[] fileExtensions = javaContentType == null ? null : javaContentType.getFileSpecs(IContentType.FILE_EXTENSION_SPEC);
+				IContentType[] contentTypes = Platform.getContentTypeManager().getAllContentTypes();
+				List extList = new ArrayList();
+				if (javaContentType != null) {
+					extList.addAll(Arrays.asList(javaContentType.getFileSpecs(IContentType.FILE_EXTENSION_SPEC)));
+				}
+				for (int i = 0; i < contentTypes.length; i++) {
+					IContentType base = contentTypes[i].getBaseType();
+					if ((base != null) && (base.equals(javaContentType))) {
+						String[] ext = contentTypes[i].getFileSpecs(IContentType.FILE_EXTENSION_SPEC);
+						extList.addAll(Arrays.asList(ext));
+					}
+				}
+				String[] fileExtensions = (String[]) extList.toArray(new String[0]);				
 				// note that file extensions contains "java" as it is defined in JDT Core's plugin.xml
 				int length = fileExtensions == null ? 0 : fileExtensions.length;
 				char[][] extensions = new char[length][];