[Proj] International 1924 Authalic Sphere needed for EASE-Grid Snow data

[Markus Neteler]

Fellow list members,

I am trying to reproject Global EASE-Grid 8-day Blended SSM/I and
MODIS Snow Cover
which are projected in EASE-Grid North (AFAIK it is EPSG 3408):
 http://nsidc.org/data/ease/ease_grid.html

Using the EPSG tool of GDAL, I obtain the following
epsg_tr.py 3408
PROJCS["NSIDC EASE-Grid North",
    GEOGCS["Unspecified datum based upon the International 1924
Authalic Sphere",
        DATUM["Not_specified_based_on_International_1924_Authalic_Sphere",
            SPHEROID["International 1924 Authalic Sphere",6371228,0,
                AUTHORITY["EPSG","7057"]],
            AUTHORITY["EPSG","6053"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.01745329251994328,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4053"]],
    UNIT["metre",1,
        AUTHORITY["EPSG","9001"]],
    PROJECTION["Lambert_Azimuthal_Equal_Area"],
    PARAMETER["latitude_of_center",90],
    PARAMETER["longitude_of_center",0],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    AUTHORITY["EPSG","3408"],
    AXIS["X",UNKNOWN],
    AXIS["Y",UNKNOWN]]

However, the International 1924 Authalic Sphere seems to be missing
from PROJ4.

Could this be officially added? Is it as simple as this code change (maybe
there is a better name to find)?

svn diff src/
Index: src/pj_ellps.c
===================================================================
--- src/pj_ellps.c      (revision 1490)
+++ src/pj_ellps.c      (working copy)
@@ -40,6 +40,7 @@
 "kaula",       "a=6378163.",  "rf=298.24", "Kaula 1961",
 "lerch",       "a=6378139.",  "rf=298.257", "Lerch 1979",
 "mprts",       "a=6397300.",  "rf=191.", "Maupertius 1738",
+"intl1924",    "a=6371228.0",  "b=6371228.0", "International 1924
Authalic Sphere",
 "new_intl",    "a=6378157.5", "b=6356772.2", "New International 1967",
 "plessis",     "a=6376523.",  "b=6355863.", "Plessis 1817 (France)",
 "SEasia",      "a=6378155.0", "b=6356773.3205", "Southeast Asia",

Best regards,
Markus Neteler