diff --git a/devel/hs-git-annex/files/patch-Build__DesktopFile.hs b/devel/hs-git-annex/files/patch-Build__DesktopFile.hs
new file mode 100644
index 000000000000..8dfb7d3275fd
--- /dev/null
+++ b/devel/hs-git-annex/files/patch-Build__DesktopFile.hs
@@ -0,0 +1,20 @@
+--- ./Build/DesktopFile.hs.orig	2013-05-03 05:20:19.000000000 +0200
++++ ./Build/DesktopFile.hs	2013-05-09 22:23:06.000000000 +0200
+@@ -42,11 +42,15 @@
+ 
+ writeFDODesktop :: FilePath -> IO ()
+ writeFDODesktop command = do
+-	datadir <- ifM systemwideInstall ( return systemDataDir, userDataDir )
++	prefix <- catchMaybeIO (getEnv "PREFIX")
++	let (sddir,scdir) = case prefix of
++			      Just p  -> (p </> "share", p </> "etc/xdg")
++			      Nothing -> (systemDataDir, systemConfigDir)
++	datadir <- ifM systemwideInstall ( return sddir, userDataDir )
+ 	installMenu command
+ 		=<< inDestDir (desktopMenuFilePath "git-annex" datadir)
+ 
+-	configdir <- ifM systemwideInstall ( return systemConfigDir, userConfigDir )
++	configdir <- ifM systemwideInstall ( return scdir, userConfigDir )
+ 	installAutoStart command 
+ 		=<< inDestDir (autoStartPath "git-annex" configdir)
+