diff --git a/modules/modpython/znc.py b/modules/modpython/znc.py
index feb98fda..5f0784f3 100644
--- a/modules/modpython/znc.py
+++ b/modules/modpython/znc.py
@@ -768,6 +768,11 @@ def find_open(modname):
         module = importlib.import_module(fullname)
     except ImportError:
         return (None, None)
+    if not isinstance(module.__loader__, ZNCModuleLoader):
+        # If modname/ is a directory, it was "loaded" using _NamespaceLoader.
+        # This is the case for e.g. modperl.
+        # https://github.com/znc/znc/issues/1757
+        return (None, None)
     return (module, os.path.join(module.__loader__._datadir, modname))
 
 def load_module(modname, args, module_type, user, network, retmsg, modpython):
diff --git a/test/integration/tests/scripting.cpp b/test/integration/tests/scripting.cpp
index e4dcfc8e..d269b1d7 100644
--- a/test/integration/tests/scripting.cpp
+++ b/test/integration/tests/scripting.cpp
@@ -279,5 +279,22 @@ TEST_F(ZNCTest, ModpythonPackage) {
     client.ReadUntil("value = b");
 }
 
+TEST_F(ZNCTest, ModpythonModperl) {
+    if (QProcessEnvironment::systemEnvironment().value(
+            "DISABLED_ZNC_PERL_PYTHON_TEST") == "1") {
+        return;
+    }
+    auto znc = Run();
+    znc->CanLeak();
+
+    auto ircd = ConnectIRCd();
+    auto client = LoginClient();
+    // https://github.com/znc/znc/issues/1757
+    client.Write("znc loadmod modpython");
+    client.ReadUntil("Loaded module modpython");
+    client.Write("znc loadmod modperl");
+    client.ReadUntil("Loaded module modperl");
+}
+
 }  // namespace
 }  // namespace znc_inttest