diff --git a/pisi/api.py b/pisi/api.py
index 30b71ce5..dcce7439 100644
--- a/pisi/api.py
+++ b/pisi/api.py
@@ -222,7 +222,7 @@ def generate_base_upgrade(A):
     # method returns the currently needed system.base component install and 
     # upgrade needs
     base = upgrade_base(A, ignore_package_conflicts = True)
-    return list(base)
+    return base
 
 def generate_conflicts(A):
     # returns the conflicting packages list of the to be installed packages.
diff --git a/pisi/operations.py b/pisi/operations.py
index 8ed97124..f35366af 100644
--- a/pisi/operations.py
+++ b/pisi/operations.py
@@ -298,7 +298,7 @@ def upgrade_base(A = set(), ignore_package_conflicts = False):
                                util.strlist(extra_upgrades))
                 G_f, upgrade_order = plan_upgrade(extra_upgrades, ignore_build)
             # return packages that must be added to any installation
-            return set(install_order + upgrade_order)
+            return install_order + upgrade_order
         else:
             ctx.ui.warning(_('Safety switch: the component system.base cannot be found'))
     return set()
@@ -325,7 +325,7 @@ def install_pkg_names(A, reinstall = False):
         ctx.ui.info(_('No packages to install.'))
         return
 
-    A |= upgrade_base(A)
+    systembase_order = upgrade_base(A)
 
     if not ctx.config.get_option('ignore_dependency'):
         G_f, order = plan_install_pkg_names(A)
@@ -333,6 +333,8 @@ def install_pkg_names(A, reinstall = False):
         G_f = None
         order = list(A)
 
+    order = systembase_order + order
+
     if len(order) > 1:
         ctx.ui.info(_("Following packages will be installed in the respective "
                       "order to satisfy dependencies:\n") + util.strlist(order))
@@ -448,7 +450,7 @@ def upgrade_pkg_names(A = []):
         ctx.ui.info(_('No packages to upgrade.'))
         return True
 
-    A |= upgrade_base(A)
+    systembase_order = upgrade_base(A)
 
     ctx.ui.debug('A = %s' % str(A))
 
@@ -458,6 +460,8 @@ def upgrade_pkg_names(A = []):
         G_f = None
         order = list(A)
 
+    order = systembase_order + order
+
     if not ctx.get_option('ignore_package_conflicts'):
         conflicts = check_conflicts(order, ctx.packagedb)