--- a/cdt/cdt_5_0_x/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CLibraryFileEntry.java	Tue Jun 16 13:57:17 2009 -0500
+++ b/cdt/cdt_5_0_x/org.eclipse.cdt.core/model/org/eclipse/cdt/core/settings/model/CLibraryFileEntry.java	Tue Jun 16 15:13:27 2009 -0500
@@ -104,6 +104,18 @@
 	}
 
 	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = super.hashCode();
+		result = prime * result + ((fSourceAttachmentPath == null) ? 0 : fSourceAttachmentPath.hashCode());
+		result = prime * result
+				+ ((fSourceAttachmentPrefixMapping == null) ? 0 : fSourceAttachmentPrefixMapping.hashCode());
+		result = prime * result
+				+ ((fSourceAttachmentRootPath == null) ? 0 : fSourceAttachmentRootPath.hashCode());
+		return result;
+	}
+
+	@Override
 	public boolean equalsByContents(ICSettingEntry entry) {
 		if(entry == this)
 			return true;

--- a/cdt/cdt_5_0_x/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/settings/model/CProjectDescriptionManager.java	Tue Jun 16 13:57:17 2009 -0500
+++ b/cdt/cdt_5_0_x/org.eclipse.cdt.core/model/org/eclipse/cdt/internal/core/settings/model/CProjectDescriptionManager.java	Tue Jun 16 15:13:27 2009 -0500
@@ -2530,14 +2530,15 @@
 			newEntries = EMPTY_LANGUAGE_SETTINGS_ENTRIES_ARRAY;
 		}
 
+		Set<ICLanguageSettingEntry> newEntrySet = new HashSet<ICLanguageSettingEntry>(Arrays.asList(newEntries));
+		Set<ICLanguageSettingEntry> oldEntrySet = new HashSet<ICLanguageSettingEntry>(Arrays.asList(oldEntries));
+		
 		// Check the removed entries.
-		for (int i = 0; i < oldEntries.length; i++) {
+		for (ICLanguageSettingEntry oldEntry : oldEntries) {
 			boolean found = false;
-			for (int j = 0; j < newEntries.length; j++) {
-				if (oldEntries[i].equals(newEntries[j])) {
-					found = true;
-					break;
-				}
+			if (newEntrySet.contains(oldEntry)) {
+				found = true;
+				break;
 			}
 			if(!found){
 				result[1] = true;
@@ -2546,13 +2547,11 @@
 		}
 
 		// Check the new entries.
-		for (int i = 0; i < newEntries.length; i++) {
+		for (ICLanguageSettingEntry newEntry : newEntries) {
 			boolean found = false;
-			for (int j = 0; j < oldEntries.length; j++) {
-				if (newEntries[i].equals(oldEntries[j])) {
-					found = true;
-					break;
-				}
+			if (oldEntrySet.contains(newEntry)) {
+				found = true;
+				break;
 			}
 			if(!found){
 				result[0] = true;