[gdal-dev] pcs.csv values don't match spatialreference.org

[David Strip]

I'm working with some files in Maryland State Plane (US foot), and 
autoIdentifyEPSG is failing. I tracked it down to what I suspect is the 
problem -

my files and spatialreference.org show the standard parallels as 38.3 
and 39.45, with a latitude of origin at 37.66666666
the pcs.csv file shows values of 38.18 and 39.27, with a latitude of 
origin at 37.4 (I don't actually know how to match the csv columns to 
the parameters, but these are the closest matching values).

Why does the pcs.csv differ from spatialreference.org, and what is the 
appropriate strategy for fixing this?

Thanks

(and apologies for a cross-posting to stackexchange, which I posted 
before I realized the difference between the two sources)

David