Index: maven-project/src/main/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssembler.java
===================================================================
--- maven-project/src/main/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssembler.java	(revision 666772)
+++ maven-project/src/main/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssembler.java	(working copy)
@@ -514,8 +514,13 @@
             uncleanPath = uncleanPath.substring( protocolIdx + 3 );
         }
 
-        if ( uncleanPath.startsWith( "/" ) )
+        if ( uncleanPath.startsWith( "//" ) )
         {
+            // preserve leading double slash for UNC paths like "file:////host/pom.xml"
+            cleanedPath += "//";
+        }
+        else if ( uncleanPath.startsWith( "/" ) )
+        {
             cleanedPath += "/";
         }
 
Index: maven-project/src/test/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssemblerTest.java
===================================================================
--- maven-project/src/test/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssemblerTest.java	(revision 666772)
+++ maven-project/src/test/java/org/apache/maven/project/inheritance/DefaultModelInheritanceAssemblerTest.java	(working copy)
@@ -221,6 +221,18 @@
         assertEquals( "Append with path adjustment failed.", "http://maven.apache.org/shared/file-management", result );
     }
 
+    public void testAppendPathUNC()
+    {
+        String parentPath = "file:////host/shared/maven-shared-parent";
+        String childPath = "file-management";
+        String pathAdjustment = null;
+
+        String result =
+            ( (DefaultModelInheritanceAssembler) assembler ).appendPath( parentPath, childPath, pathAdjustment, true );
+
+        assertEquals( "file:////host/shared/maven-shared-parent/file-management", result );
+    }
+
     public void testDistributionManagementInheritance()
     {
         Model parent = makeBaseModel( "parent" );