Rakefile in rio-0.3.1 vs Rakefile in rio-0.3.2

@@ -176,10 +176,10 @@
   proju = rio(repos,PKG::NAME,'trunk') 
   relu  = rio(repos,PKG::NAME,'tags','release-') + PKG::VERSION 
   relo =`svn list #{relu.to_url}`
   if relo.size > 0
     $stderr.puts "Release #{relu.to_url} exists!"
-    exit -1
+    exit(-1)
   end
   msg = "Release #{PKG::VERSION} of #{PKG::NAME}"
   cmd = sprintf('svn copy %s %s -m "%s"',proju.to_url, relu.to_url, msg)
   sh cmd
 end