[Haskell-cafe] Strange cabal failure

In trying to install the lens package, it eventually tries to install transformers-compat-0.1.1.1 which in turn depends on transformers-0.3.0.0 -- however that asksk for transformers-0.3.0.0-3006d6ea13a2c10770bffd4de7a96dc9 which 1) is weird, and 2) doesn't exist!' What gives? Jacques