diff --git a/mig/shared/base.py b/mig/shared/base.py
index 64f12b370..b21d4ae6f 100644
--- a/mig/shared/base.py
+++ b/mig/shared/base.py
@@ -36,6 +36,7 @@
 import re
 
 # IMPORTANT: do not import any other MiG modules here - to avoid import loops
+from mig.shared.compat import PY2
 from mig.shared.defaults import default_str_coding, default_fs_coding, \
     keyword_all, keyword_auto, sandbox_names, _user_invisible_files, \
     _user_invisible_dirs, _vgrid_xgi_scripts, cert_field_order, csrf_field, \
@@ -496,7 +497,7 @@ def is_unicode(val):
     return (type(u"") == type(val))
 
 
-def force_utf8(val, highlight=''):
+def _force_utf8_py2(val, highlight=''):
     """Internal helper to encode unicode strings to utf8 version. Actual
     changes are marked out with the highlight string if given.
     """
@@ -507,6 +508,31 @@ def force_utf8(val, highlight=''):
         return val
     return "%s%s%s" % (highlight, val.encode("utf8"), highlight)
 
+def _force_utf8_py3(val, highlight='', stringify=True):
+    """Internal helper to encode unicode strings to utf8 version. Actual
+    changes are marked out with the highlight string if given.
+    The optional stringify turns ALL values including numbers into string.
+    """
+    # We run into all kind of nasty encoding problems if we mix
+    if not isinstance(val, basestring):
+        if stringify:
+            val = "%s" % val
+        else:
+            return val
+    if not is_unicode(val):
+        return val
+    if is_unicode(highlight):
+        hl_utf = highlight.encode("utf8")
+    else:
+        hl_utf = highlight
+    return (b"%s%s%s" % (hl_utf, val.encode("utf8"), hl_utf))
+
+
+if PY2:
+    force_utf8 = _force_utf8_py2
+else:
+    force_utf8 = _force_utf8_py3
+
 
 def force_utf8_rec(input_obj, highlight=''):
     """Recursive object conversion from unicode to utf8: useful to convert e.g.
diff --git a/mig/shared/safeinput.py b/mig/shared/safeinput.py
index 592250755..e91937d8c 100644
--- a/mig/shared/safeinput.py
+++ b/mig/shared/safeinput.py
@@ -58,7 +58,7 @@
     from html import escape as escape_html
 assert escape_html is not None
 
-from mig.shared.base import force_unicode, force_utf8
+from mig.shared.base import force_unicode, force_native_str
 from mig.shared.defaults import src_dst_sep, username_charset, \
     username_max_length, session_id_charset, session_id_length, \
     subject_id_charset, subject_id_min_length, subject_id_max_length, \
@@ -2294,7 +2294,7 @@ def __init__(self, value):
     def __str__(self):
         """Return string representation"""
 
-        return force_utf8(force_unicode(self.value))
+        return force_native_str(self.value)
 
 
 def main(_exit=sys.exit, _print=print):
diff --git a/tests/test_mig_shared_base.py b/tests/test_mig_shared_base.py
new file mode 100644
index 000000000..82145cb20
--- /dev/null
+++ b/tests/test_mig_shared_base.py
@@ -0,0 +1,60 @@
+# -*- coding: utf-8 -*-
+#
+# --- BEGIN_HEADER ---
+#
+# test_mig_shared_base - unit test of the corresponding mig shared module
+# Copyright (C) 2003-2024  The MiG Project by the Science HPC Center at UCPH
+#
+# This file is part of MiG.
+#
+# MiG is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# MiG is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+# USA.
+#
+# --- END_HEADER ---
+#
+
+"""Unit test base functions"""
+
+import binascii
+import codecs
+import os
+import sys
+
+from tests.support import PY2, MigTestCase, testmain
+
+from mig.shared.base import force_utf8
+
+DUMMY_STRING = "foo bÆr baz"
+DUMMY_UNICODE = u'UniCode123½¾µßðþđŋħĸþł@ª€£$¥©®'
+
+
+class MigSharedBase(MigTestCase):
+    """Unit tests of fucntions within the mig.shared.base module."""
+
+    def test_force_utf8_on_string(self):
+        actual = force_utf8(DUMMY_STRING)
+
+        self.assertIsInstance(actual, bytes)
+        self.assertEqual(binascii.hexlify(actual), b'666f6f2062c386722062617a')
+
+    def test_force_utf8_on_unicode(self):
+        actual = force_utf8(DUMMY_UNICODE)
+
+        self.assertIsInstance(actual, bytes)
+        self.assertEqual(actual, codecs.encode(DUMMY_UNICODE, 'utf8'))
+
+
+if __name__ == '__main__':
+    testmain()