--- /dev/null
+Upstream-Status: Backport
+
+--- a/subversion/mod_dav_svn/liveprops.c
++++ b/subversion/mod_dav_svn/liveprops.c
+@@ -410,7 +410,8 @@ insert_prop(const dav_resource *resource
+ svn_filesize_t len = 0;
+
+ /* our property, but not defined on collection resources */
+- if (resource->collection || resource->baselined)
++ if (resource->type == DAV_RESOURCE_TYPE_ACTIVITY
++ || resource->collection || resource->baselined)
+ return DAV_PROP_INSERT_NOTSUPP;
+
+ serr = svn_fs_file_length(&len, resource->info->root.root,
+@@ -434,7 +435,9 @@ insert_prop(const dav_resource *resource
+ svn_string_t *pval;
+ const char *mime_type = NULL;
+
+- if (resource->baselined && resource->type == DAV_RESOURCE_TYPE_VERSION)
++ if (resource->type == DAV_RESOURCE_TYPE_ACTIVITY
++ || (resource->baselined
++ && resource->type == DAV_RESOURCE_TYPE_VERSION))
+ return DAV_PROP_INSERT_NOTSUPP;
+
+ if (resource->type == DAV_RESOURCE_TYPE_PRIVATE