### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core.tests.model
Index: src/org/eclipse/jdt/core/tests/model/NameLookupTests2.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/NameLookupTests2.java,v
retrieving revision 1.26
diff -u -r1.26 NameLookupTests2.java
--- src/org/eclipse/jdt/core/tests/model/NameLookupTests2.java	27 Jun 2008 16:02:40 -0000	1.26
+++ src/org/eclipse/jdt/core/tests/model/NameLookupTests2.java	20 Apr 2009 17:16:15 -0000
@@ -14,6 +14,7 @@
 
 import org.eclipse.core.resources.IWorkspaceRunnable;
 import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.IPath;
 import org.eclipse.core.runtime.IProgressMonitor;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.jdt.core.*;
@@ -250,6 +251,25 @@
 	}
 }
 /*
+ * Ensure that finding a package fragment with a path with a length equals to an external jar path length + 1
+ * (regression test for bug 266771 NameLookup.findPackageFragment returns very incorrect package fragments)
+ */
+public void testFindPackageFragment2() throws CoreException {
+	try {
+		JavaProject project = (JavaProject)createJavaProject("P", new String[0], new String[] {"JCL_LIB"}, "bin");
+		NameLookup nameLookup =getNameLookup(project);
+		IPath pathToSearch = new Path(getExternalJCLPathString() + 'a');
+		IPackageFragment pkg = nameLookup.findPackageFragment(pathToSearch);
+		assertElementEquals(
+			"Unexpected package",
+			"<null>",
+			pkg);
+	} finally {
+		deleteProject("P");
+	}
+}
+
+/*
  * Ensure that a member type with a name ending with a dollar and a number is found
  * (regression test for bug 103466 Stack Overflow: Requesting Java AST from selection)
  */
#P org.eclipse.jdt.core
Index: model/org/eclipse/jdt/internal/core/NameLookup.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/NameLookup.java,v
retrieving revision 1.125
diff -u -r1.125 NameLookup.java
--- model/org/eclipse/jdt/internal/core/NameLookup.java	7 Mar 2009 00:58:57 -0000	1.125
+++ model/org/eclipse/jdt/internal/core/NameLookup.java	20 Apr 2009 17:16:17 -0000
@@ -414,8 +414,7 @@
 					continue;
 				}
 				IPath rootPath = root.getPath();
-				int matchingCount = rootPath.matchingFirstSegments(path);
-				if (matchingCount != 0) {
+				if (rootPath.isPrefixOf(path)) {
 					String name = path.toOSString();
 					// + 1 is for the File.separatorChar
 					name = name.substring(rootPath.toOSString().length() + 1, name.length());