diff --git a/Changelog.md b/Changelog.md
--- a/Changelog.md
+++ b/Changelog.md
@@ -1,6 +1,11 @@
 # Changelog
 
+## Version 0.1.1
+
+ * Filter wrong characters in account number and blz in Finance.IBAN.Germany,
+ * Update text dependency.
+
 ## Version 0.1
 
-Initial version with validator for IBANs. Includes rudimentary German legacy account to iban functionality.
+Initial version with validator for IBANs. Includes rudimentary German legacy account to IBAN functionality.
 
diff --git a/iban.cabal b/iban.cabal
--- a/iban.cabal
+++ b/iban.cabal
@@ -2,10 +2,10 @@
 -- see http://haskell.org/cabal/users-guide/
 
 name:                iban
-version:             0.1.0.0
+version:             0.1.1.0
 synopsis:            Validate and generate IBANs
 description:         A library to validate and generate (for now only German) IBANs.
-homepage:            https://github.com/ibotty/haskell-iban
+homepage:            https://github.com/ibotty/iban
 license:             BSD3
 license-file:        LICENSE
 author:              Tobias Florek
@@ -27,25 +27,25 @@
   other-extensions:    OverloadedStrings
   build-depends:       base >=4.5 && <4.8
                      , containers >=0.3 && <0.6
-                     , text >=0.11 && <1.2
-                     , unordered-containers ==0.2.*
                      , iso3166-country-codes
+                     , text >=0.11 && <1.3
+                     , unordered-containers ==0.2.*
   hs-source-dirs:      src
   default-language:    Haskell2010
 
 test-suite tests
   other-extensions:    OverloadedStrings
   build-depends:       base
+                     , HUnit
                      , iban
-                     , text
                      , tasty
                      , tasty-hunit
-                     , HUnit
+                     , text
   hs-source-dirs:      test
-  main-is:             Main.hs
-  other-modules:       IBANRegistryExamples
-  default-language:    Haskell2010
-  type:                exitcode-stdio-1.0
+  main-is:           Main.hs
+  other-modules:     IBANRegistryExamples
+  default-language:  Haskell2010
+  type:              exitcode-stdio-1.0
 
 -- flag maintenance-tools
 --   description:       Build tools to generate data files from original sources
diff --git a/src/Finance/IBAN/Germany.hs b/src/Finance/IBAN/Germany.hs
--- a/src/Finance/IBAN/Germany.hs
+++ b/src/Finance/IBAN/Germany.hs
@@ -10,6 +10,7 @@
   ) where
 
 import Control.Arrow (second)
+import Data.Char (isDigit)
 import Data.Text (Text)
 import Finance.IBAN.Internal
 import Finance.IBAN.Germany.Core
@@ -20,7 +21,7 @@
 import qualified Data.Text as T
 
 ibanFromLegacy :: BLZ -> AccountNr -> (IBAN, Maybe BIC)
-ibanFromLegacy blz account = (IBAN (ibanWithChecksum checksum), mBIC)
+ibanFromLegacy blz' account' = (IBAN (ibanWithChecksum checksum), mBIC)
   where
     mBIC = HM.lookup blz blzBICs
     ibanWithChecksum c = T.concat [cc, c, blz, accountStr]
@@ -30,6 +31,9 @@
     checksum = T.pack $ case show (98 - mod97_10 ibanCandidate) of
                           [d,d'] -> [ d,  d']
                           [d']   -> ['0', d']
+    filterNumbers = T.filter isDigit
+    blz = filterNumbers blz'
+    account = filterNumbers account'
 
 legacyFromIBAN :: IBAN -> (BLZ, AccountNr)
 legacyFromIBAN = second (T.dropWhile (== '0')) . T.splitAt 8 . T.drop 4 . rawIBAN
diff --git a/test/Main.hs b/test/Main.hs
--- a/test/Main.hs
+++ b/test/Main.hs
@@ -7,7 +7,6 @@
 import Finance.IBAN.Germany
 import Test.Tasty
 import Test.Tasty.HUnit
-import Test.HUnit
 
 import qualified IBANRegistryExamples as R
 import qualified Data.Text as T