diff --git a/pyproject-rpm-macros.spec b/pyproject-rpm-macros.spec
index cd6b722..f6ec517 100644
--- a/pyproject-rpm-macros.spec
+++ b/pyproject-rpm-macros.spec
@@ -6,7 +6,7 @@ License:        MIT
 
 # Keep the version at zero and increment only release
 Version:        0
-Release:        46%{?dist}
+Release:        47%{?dist}
 
 # Macro files
 Source001:      macros.pyproject
@@ -113,6 +113,9 @@ export HOSTNAME="rpmbuild"  # to speedup tox in network-less mock, see rhbz#1856
 %license LICENSE
 
 %changelog
+* Thu Sep 09 2021 Miro Hrončok <mhroncok@redhat.com> - 0-47
+- %%pyproject_save_files: Expand the namespace error message, also display it with /
+
 * Fri Jul 23 2021 Miro Hrončok <miro@hroncok.cz> - 0-46
 - %%pyproject_buildrequires now fails when it encounters an invalid requirement
 - Fixes: rhbz#1983053
diff --git a/pyproject_save_files.py b/pyproject_save_files.py
index dac8b3f..b9d656f 100644
--- a/pyproject_save_files.py
+++ b/pyproject_save_files.py
@@ -381,16 +381,25 @@ def parse_varargs(varargs):
         >>> parse_varargs(['mod', 'mod.*'])
         Traceback (most recent call last):
           ...
-        ValueError: Attempted to use a namespaced package with dot in the glob: mod.*. ...
+        ValueError: Attempted to use a namespaced package with . in the glob: mod.*. ...
 
         >>> parse_varargs(['my.bad', '+bad'])
         Traceback (most recent call last):
           ...
-        ValueError: Attempted to use a namespaced package with dot in the glob: my.bad. ...
+        ValueError: Attempted to use a namespaced package with . in the glob: my.bad. ...
+
+        >>> parse_varargs(['mod/submod'])
+        Traceback (most recent call last):
+          ...
+        ValueError: Attempted to use a namespaced package with / in the glob: mod/submod. ...
     """
     include_auto = False
     globs = set()
-
+    namespace_error_template = (
+        "Attempted to use a namespaced package with {symbol} in the glob: {arg}. "
+        "That is not (yet) supported. Use {top} instead and see "
+        "https://bugzilla.redhat.com/1935266 for details."
+    )
     for arg in varargs:
         if arg.startswith("+"):
             if arg == "+auto":
@@ -399,11 +408,10 @@ def parse_varargs(varargs):
                 raise ValueError(f"Invalid argument: {arg}")
         elif "." in arg:
             top, *_ = arg.partition(".")
-            msg = (
-                f"Attempted to use a namespaced package with dot in the glob: {arg}. "
-                f"That is not (yet) supported. Use {top} instead and/or file a Bugzilla explaining your use case."
-            )
-            raise ValueError(msg)
+            raise ValueError(namespace_error_template.format(symbol=".", arg=arg, top=top))
+        elif "/" in arg:
+            top, *_ = arg.partition("/")
+            raise ValueError(namespace_error_template.format(symbol="/", arg=arg, top=top))
         else:
             globs.add(arg)