Index: smart/backends/rpm/metadata.py
===================================================================
--- smart/backends/rpm/metadata.py	(revision 896)
+++ smart/backends/rpm/metadata.py	(working copy)
@@ -195,7 +195,8 @@
 
                 elif tag == SIZE:
                     info["size"] = int(elem.get("package"))
-                    info["installed_size"] = int(elem.get("installed"))
+                    if elem.get("installed"):
+                        info["installed_size"] = int(elem.get("installed"))
 
                 elif tag == CHECKSUM:
                     info[elem.get("type")] = elem.text