Hasktags misses symbol

(not sure I filed this bug appropriately. I belive hasktags came as part of the ghc-6.6 binary package. Please advise if there's a better place)

Hasktags is missing an obvious symbol.

$ darcs get --partial http://happs.org/HAppS

$ cd HAppS/src

$ hasktags -c `find . -name '*.hs' |grep -v _darcs` 

$ grep boolM                                            # <- not found 

$ grep boolM `find . -name '*.hs' |grep -v _darcs`      # <- found