diff --git a/pisi/archive.py b/pisi/archive.py
index 2517cb07..0194407c 100644
--- a/pisi/archive.py
+++ b/pisi/archive.py
@@ -557,7 +557,11 @@ class Archive:
                     'bzip2':    ArchiveBzip2,
                     'binary':   ArchiveBinary}
 
-        self.archive = handlers.get(arch_type)(file_path, arch_type)
+        handler = handlers.get(arch_type)
+        if handler is None:
+            raise UnknownArchiveType
+
+        self.archive = handler(file_path, arch_type)
 
     def unpack(self, target_dir, clean_dir=False):
         self.archive.unpack(target_dir, clean_dir)
diff --git a/pisi/sourcearchive.py b/pisi/sourcearchive.py
index 7e989277..8c95ad7b 100644
--- a/pisi/sourcearchive.py
+++ b/pisi/sourcearchive.py
@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 #
-# Copyright (C) 2005 - 2007, TUBITAK/UEKAE
+# Copyright (C) 2005-2010, TUBITAK/UEKAE
 #
 # This program is free software; you can redistribute it and/or modify it under
 # the terms of the GNU General Public License as published by the Free
@@ -119,6 +119,11 @@ class SourceArchive:
         if not util.check_file_hash(self.archiveFile, self.archive.sha1sum):
             raise Error, _("unpack: check_file_hash failed")
 
-        archive = pisi.archive.Archive(self.archiveFile, self.archive.type)
+        try:
+            archive = pisi.archive.Archive(self.archiveFile, self.archive.type)
+        except pisi.archive.UnknownArchiveType:
+            raise Error(_("Unknown archive type '%s' is given for '%s'.")
+                        % (self.archive.type, self.url.filename()))
+
         target_dir = os.path.join(self.pkg_work_dir, self.archive.target or "")
         archive.unpack(target_dir, clean_dir)