diff --git a/pisi/util.py b/pisi/util.py
index d94cbb58..35a45bf6 100644
--- a/pisi/util.py
+++ b/pisi/util.py
@@ -479,7 +479,7 @@ def clean_locks(top = '.'):
 def package_name(name, version, release, build):
     fn = name + '-' + version + '-' + release
     if build:
-        fn += '-' + build
+        fn += '-' + str(build)
     fn += ctx.const.package_suffix
     return fn