diff --git a/osc/babysitter.py b/osc/babysitter.py
index 4129aea2..54668f08 100644
--- a/osc/babysitter.py
+++ b/osc/babysitter.py
@@ -172,7 +172,7 @@ def run(prg, argv=None):
         print(e.msg, file=sys.stderr)
         traceback.print_exc(file=sys.stderr)
     except oscerr.PackageError as e:
-        print(e.msg, file=sys.stderr)
+        print(str(e), file=sys.stderr)
     except PackageError as e:
         print(f'{e.fname}:', e.msg, file=sys.stderr)
     except RPMError as e:
diff --git a/osc/core.py b/osc/core.py
index a23ff215..5194ce0c 100644
--- a/osc/core.py
+++ b/osc/core.py
@@ -6133,6 +6133,34 @@ def branch_pkg(
     """
     Branch a package (via API call)
     """
+
+    # BEGIN: Error out on branching scmsync packages; this should be properly handled in the API
+
+    # read src_package meta
+    m = b"".join(show_package_meta(apiurl, src_project, src_package))
+    root = ET.fromstring(m)
+
+    devel_project = None
+    devel_package = None
+    if not nodevelproject:
+        devel_node = root.find("devel")
+        if devel_node is not None:
+            devel_project = devel_node.get("project")
+            devel_package = devel_node.get("package", src_package)
+        if devel_project:
+            # replace src_package meta with devel_package meta because we're about branch from devel
+            m = b"".join(show_package_meta(apiurl, devel_project, devel_package))
+            root = ET.fromstring(m)
+
+    # error out if we're branching a scmsync package (we'd end up with garbage anyway)
+    if root.find("scmsync") is not None:
+        msg = "Cannot branch a package with <scmsync> set."
+        if devel_project:
+            raise oscerr.PackageError(devel_project, devel_package, msg)
+        raise oscerr.PackageError(src_project, src_package, msg)
+
+    # END: Error out on branching scmsync packages; this should be properly handled in the API
+
     query = {'cmd': 'branch'}
     if nodevelproject:
         query['ignoredevel'] = '1'