diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 2c97f02238adb1e86c67d4b6f29b14299d57d89b..aa5c58c4d147d15f11d072363f73564780ea3a85 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,5 +1,5 @@
 variables:
-  PYTHON: python3.11
+  PYTHON: python3.12
 
 default:
   image: debian:testing-slim
diff --git a/osc_plugin_dput/main.py b/osc_plugin_dput/main.py
index 1ff6ed8a2eeefa185cfc380192624407761bd5f8..ac8a533b7c23028ca2f56741819adb604b89c214 100644
--- a/osc_plugin_dput/main.py
+++ b/osc_plugin_dput/main.py
@@ -192,13 +192,18 @@ def do_dput(self, subcmd, opts, *args):
         superseded = set()
         retained = set()
 
+        # osc <1.6.1 doesn't automatically escape path members.
+        should_escape_filename = osc.core.makeurl('', ['+']) == '/+'
+
         for f in remote_file_list.keys():
             if f.endswith('.dsc'):
                 u = osc.core.makeurl(conf.config['apiurl'],
                                      ['source',
                                       proj_name,
                                       package_name,
-                                      pathname2url(f)],
+                                      pathname2url(f)
+                                        if should_escape_filename
+                                        else f],
                                      query={})
 
                 remote_dsc = Dsc(osc.core.streamfile(u, bufsize='line'))