diff --git a/Distribution/Cab/Commands.hs b/Distribution/Cab/Commands.hs
--- a/Distribution/Cab/Commands.hs
+++ b/Distribution/Cab/Commands.hs
@@ -8,7 +8,7 @@
 import Control.Applicative hiding (many)
 import Control.Monad
 import Data.Char
-import Data.List (isPrefixOf, intercalate)
+import Data.List (isPrefixOf, isSuffixOf, intercalate)
 import qualified Data.Map as M
 import Distribution.Cab.GenPaths
 import Distribution.Cab.PkgDB
@@ -97,10 +97,29 @@
         mapM_ (hPutStrLn stderr . fullNameOfPkgInfo) (init sortedPkgs)
       else do
         unless doit $ putStrLn "The following packages are deleted without the \"-n\" option."
-        mapM_ (unregister doit opts . pairNameOfPkgInfo) sortedPkgs
+        mapM_ (purge doit opts . pairNameOfPkgInfo) sortedPkgs
   where
     onlyOne = OptRecursive `notElem` opts
     doit = OptNoharm `notElem` opts
+
+purge :: Bool -> [Option] -> (String,String) -> IO ()
+purge doit opts (name,ver) = do
+--    putStrLn $ "Deleting " ++ name ++ " " ++ ver
+    sandboxOpts <- (makeOptList . getSandboxOpts2) <$> getSandbox
+    libdirs <- queryGhcPkg sandboxOpts "library-dirs"
+    haddoc  <- cutTrailing "html" `fmap` queryGhcPkg sandboxOpts "haddock-html"
+    unregister doit opts (name,ver)
+    putStrLn $ unwords ["Deleting dirs:", libdirs, haddoc]
+    when doit . void . system . unwords $ ["rm -rf ", libdirs, haddoc]
+  where
+    makeOptList "" = []
+    makeOptList x  = [x]
+    queryGhcPkg sandboxOpts field = do
+        let options = ["field"] ++ sandboxOpts ++ [name ++ "-" ++ ver, field]
+        unwords . tail . words <$> readProcess "ghc-pkg" options ""
+    cutTrailing suffix s
+      | suffix `isSuffixOf` s = reverse . drop (length suffix) . reverse $ s
+      | otherwise             = s
 
 unregister :: Bool -> [Option] -> (String,String) -> IO ()
 unregister doit _ (name,ver) =
diff --git a/cab.cabal b/cab.cabal
--- a/cab.cabal
+++ b/cab.cabal
@@ -1,5 +1,5 @@
 Name:                   cab
-Version:                0.2.6
+Version:                0.2.7
 Author:                 Kazu Yamamoto <kazu@iij.ad.jp>
 Maintainer:             Kazu Yamamoto <kazu@iij.ad.jp>
 License:                BSD3