diff --git a/attic/platform_linux.pyx b/attic/platform_linux.pyx
index b0479b89a..ee0f0bd59 100644
--- a/attic/platform_linux.pyx
+++ b/attic/platform_linux.pyx
@@ -65,9 +65,11 @@ cdef acl_numeric_ids(acl):
         if entry:
             type, name, permission = entry.split(':')
             if name and type == 'user':
-                entries.append(':'.join([type, str(user2uid(name, name)), permission]))
+                uid = str(user2uid(name, name))
+                entries.append(':'.join([type, uid, permission, uid]))
             elif name and type == 'group':
-                entries.append(':'.join([type, str(group2gid(name, name)), permission]))
+                gid = str(group2gid(name, name))
+                entries.append(':'.join([type, gid, permission, gid]))
             else:
                 entries.append(entry)
     return ('\n'.join(entries)).encode('ascii')
@@ -94,12 +96,12 @@ def acl_get(path, item, numeric_owner=False):
         if access_acl:
             access_text = acl_to_text(access_acl, NULL)
             if access_text:
-                item[b'acl_access'] = acl_append_numeric_ids(access_text)
+                item[b'acl_access'] = converter(access_text)
         default_acl = acl_get_file(<bytes>os.fsencode(path), ACL_TYPE_DEFAULT)
         if default_acl:
             default_text = acl_to_text(default_acl, NULL)
             if default_text:
-                item[b'acl_default'] = acl_append_numeric_ids(default_text)
+                item[b'acl_default'] = converter(default_text)
     finally:
         acl_free(default_text)
         acl_free(default_acl)
diff --git a/attic/testsuite/platform.py b/attic/testsuite/platform.py
index af64dc0f3..6625efeb5 100644
--- a/attic/testsuite/platform.py
+++ b/attic/testsuite/platform.py
@@ -44,20 +44,26 @@ class PlatformLinuxTestCase(AtticTestCase):
     def tearDown(self):
         shutil.rmtree(self.tmpdir)
 
-    def get_acl(self, path):
+    def get_acl(self, path, numeric_owner=False):
         item = {}
-        acl_get(path, item)
+        acl_get(path, item, numeric_owner=numeric_owner)
         return item
 
-    def set_acl(self, path, access=None, default=None):
+    def set_acl(self, path, access=None, default=None, numeric_owner=False):
         item = {b'acl_access': access, b'acl_default': default}
-        acl_set(path, item)
+        acl_set(path, item, numeric_owner=numeric_owner)
 
     def test_access_acl(self):
         file = tempfile.NamedTemporaryFile()
         self.assert_equal(self.get_acl(file.name), {})
-        self.set_acl(file.name, access=ACCESS_ACL)
-        self.assert_equal(self.get_acl(file.name)[b'acl_access'], ACCESS_ACL)
+        self.set_acl(file.name, access=b'user::rw-\ngroup::r--\nmask::rw-\nother::---\nuser:root:rw-:9999\ngroup:root:rw-:9999\n', numeric_owner=False)
+        self.assert_in(b'user:root:rw-:0', self.get_acl(file.name)[b'acl_access'])
+        self.assert_in(b'group:root:rw-:0', self.get_acl(file.name)[b'acl_access'])
+        self.assert_in(b'user:0:rw-:0', self.get_acl(file.name, numeric_owner=True)[b'acl_access'])
+        file2 = tempfile.NamedTemporaryFile()
+        self.set_acl(file2.name, access=b'user::rw-\ngroup::r--\nmask::rw-\nother::---\nuser:root:rw-:9999\ngroup:root:rw-:9999\n', numeric_owner=True)
+        self.assert_in(b'user:9999:rw-:9999', self.get_acl(file2.name)[b'acl_access'])
+        self.assert_in(b'group:9999:rw-:9999', self.get_acl(file2.name)[b'acl_access'])
 
     def test_default_acl(self):
         self.assert_equal(self.get_acl(self.tmpdir), {})
diff --git a/attic/xattr.py b/attic/xattr.py
index 7412c6ae8..5e2b11a69 100644
--- a/attic/xattr.py
+++ b/attic/xattr.py
@@ -66,7 +66,7 @@ if sys.platform.startswith('linux'):
         n2 = _check(func(path, namebuf, n), path)
         if n2 != n:
             raise Exception('listxattr failed')
-        return [os.fsdecode(name) for name in namebuf.raw.split(b'\0')[:-1]]
+        return [os.fsdecode(name) for name in namebuf.raw.split(b'\0')[:-1] if not n.startswith(b'system.posix_acl_')]
 
     def getxattr(path, name, *, follow_symlinks=True):
         name = os.fsencode(name)