diff --git a/CHANGES b/CHANGES
--- a/CHANGES
+++ b/CHANGES
@@ -1,1 +1,6 @@
-* 0.1.0 First public release
+* 0.1.1.0 Bug-fix release
+  
+  - fixed: automatically create output directory, if it does not exist
+  - fixed: wrong flags given in help message for starting interactive mode
+
+* 0.1.0.0 First public release
diff --git a/src/Main.hs b/src/Main.hs
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -231,7 +231,7 @@
   let userGuidePath = examplePath </> "UserGuide.spthy"
       csf12Path = examplePath </> "csf12" </> "*.spthy"
       csf12Cmd  = programName ++ " --prove -Ocase-studies +RTS -N -RTS " ++ csf12Path 
-      csf12Cmd' = programName ++ " --interactive +RTS -N -RTS " ++ csf12Path 
+      csf12Cmd' = programName ++ " interactive +RTS -N -RTS " ++ csf12Path 
       separator = putStrLn $ replicate shortLineWidth '-'
       putPath info path = putStrLn info >> putStrLn ("  " ++ path ++ "\n")
   separator
@@ -286,7 +286,7 @@
     --------------------
 
     writeThy thyString = case optOutPath of
-      Just outPath -> writeFile outPath thyString
+      Just outPath -> writeFileWithDirs outPath thyString
       Nothing      -> return ()
     
     -- Output file name, if output is desired.
@@ -548,7 +548,7 @@
                 putStrLn $ "analyzing: " ++ inFile
                 putStrLn $ ""
                 let outFile = mkOutPath inFile
-                summary <- writeWithSummary (writeFile outFile) outFile
+                summary <- writeWithSummary (writeFileWithDirs outFile) outFile
                 putStrLn $ replicate shortLineWidth '-'
                 putStrLn $ renderDoc summary
                 putStrLn $ ""
@@ -607,6 +607,12 @@
 ------------------------------------------------------------------------------
 -- Utility functions
 ------------------------------------------------------------------------------
+
+-- | Write a file and ensure that its containing directory exists.
+writeFileWithDirs :: FilePath -> String -> IO ()
+writeFileWithDirs file output = do
+    createDirectoryIfMissing True (takeDirectory file)
+    writeFile file output
 
 -- | Get the string constituting the command line.
 getCommandLine :: IO String
diff --git a/tamarin-prover.cabal b/tamarin-prover.cabal
--- a/tamarin-prover.cabal
+++ b/tamarin-prover.cabal
@@ -1,7 +1,7 @@
 cabal-version:      >= 1.8
 build-type:         Simple
 name:               tamarin-prover
-version:            0.1.0.0
+version:            0.1.1.0
 license:            GPL
 license-file:       LICENSE
 category:           Theorem Provers