diff --git a/plugins.cabal b/plugins.cabal
--- a/plugins.cabal
+++ b/plugins.cabal
@@ -1,5 +1,5 @@
 name:               plugins
-version:            1.5.1.3
+version:            1.5.1.4
 homepage:           http://code.haskell.org/~dons/code/hs-plugins
 synopsis:           Dynamic linking for Haskell and C objects
 description:        Dynamic linking and runtime evaluation of Haskell,
@@ -8,7 +8,9 @@
                     Described in the papers:
 
                      * /Plugging Haskell In/, <http://www.cse.unsw.edu.au/~dons/papers/PSSC04.html>
+
                      * /Dynamic Applications from the Ground Up/, <http://www.cse.unsw.edu.au/~dons/papers/SC05.html>
+
                      * /Dynamic Extension of Typed Functional Languages/.
 
 category:           System
diff --git a/src/System/Plugins/Env.hs b/src/System/Plugins/Env.hs
--- a/src/System/Plugins/Env.hs
+++ b/src/System/Plugins/Env.hs
@@ -58,7 +58,7 @@
 
 import Data.IORef               ( writeIORef, readIORef, newIORef, IORef() )
 import Data.Maybe               ( isJust, isNothing, fromMaybe )
-import Data.List                ( nub )
+import Data.List                ( (\\), nub, )
 
 import System.IO.Unsafe         ( unsafePerformIO )
 import System.Directory         ( doesFileExist )
@@ -299,8 +299,8 @@
         let fm = emptyFM -- new FM for this package.conf
         in foldr addOnePkg fm ps' : ls
     where 
-      -- we add each package with and without it's version number
-      addOnePkg p fm' = addToPkgEnvs (addToPkgEnvs fm' (display $ sourcePackageId p) p)
+      -- we add each package with and without it's version number and with the full installedPackageId
+      addOnePkg p fm' = addToPkgEnvs (addToPkgEnvs (addToPkgEnvs fm' (display $ sourcePackageId p) p) (display $ installedPackageId p) p)
                                      (packageName p) p
       
       -- if no version number specified, pick the higher version
@@ -361,10 +361,13 @@
 -- up to loadObject not to load the same ones twice...
 --
 lookupPkg :: PackageName -> IO ([FilePath],[FilePath])
-lookupPkg p = do 
+lookupPkg pn = go [] pn
+    where
+      go :: [PackageName] -> PackageName -> IO ([FilePath],[FilePath])
+      go seen p = do 
         (ps, (f, g)) <- lookupPkg' p
         static <- isStaticPkg p
-        (f', g') <- liftM unzip $ mapM lookupPkg ps
+        (f', g') <- liftM unzip $ mapM (go (nub $ seen ++ ps)) (ps \\ seen)
         return $ (nub $ (concat f') ++ f, if static then [] else nub $ (concat g') ++ g)
 
 data LibrarySpec