overlapping instances and modules

[Iavor S. Diatchki]

hello,
i am a bit stuck on the following problem,
which seems to be GHC related.
consider the following two modules:

 > {-# OPTIONS -fglasgow-exts -fallow-overlapping-instances #-}
 > module Test where
 >
 > data T m a = T (m a)
 >
 > class C m where get :: m a
 >
 > instance C (T m)
 > instance C m => C (t m)
 >
 > obs :: T [] Int
 > obs = get

 > module Test1 where
 >
 > import Test
 >
 > obs' :: T [] Int
 > obs' = get

i can load the first one (Test) without problems,
but when i load the second one (Test1) a get the error:
Test1.hs:6:
    No instance for (C [])
      arising from use of `get' at Test1.hs:6
    In the definition of `obs'': obs' = get

this seems to indicate that the second instance is being used,
but i cannot figure out why.  am i doing something silly here?

-iavor
ps: i am not on the GHC users list so please cc me if you replay there




-- 
==================================================
| Iavor S. Diatchki, Ph.D. student               | 
| Department of Computer Science and Engineering |
| School of OGI at OHSU                          |
| http://www.cse.ogi.edu/~diatchki               |
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