Composable memory transactions are a new communication abstraction for Concurrent Haskell which provides the programmer with a composable communication concept. Unfortunately, composable memory transactions are implemented as external functions for ghc version 6.4 and not available for other implementations of Concurrent Haskell. We present an implementation of memory transactions within Concurrent Haskell. The presented library can be executed within older ghc versions as well as with the popular Hugs system. Benchmarks show that our library performes well. Furthermore, our (high-level) implementation can be extended and maintained more easily than the low-level implementation provided by ghc 6.4.