lower integer bound not supported

According to documentation (from 9.1 to 9.5) the supported
integer ranges are these ones:

 smallint  2 bytes   -32768 to +32767
  integer  4 bytes   -2147483648 to +2147483647
   bigint  8 bytes   -9223372036854775808 to +9223372036854775807

But the lowest bound is not really supported:

  # select -32768::int2;
  ERROR:  smallint out of range
  # select -2147483648::int4;
  ERROR:  integer out of range
  # select -9223372036854775808::int8;
  ERROR:  bigint out of range

This happens with server versions 9.1.22, 9.3.6 and 9.5(unspecified).

Is it the code or the documentation being broken ?
To me, the documentation makes the most sense, and the code is broken.

--strk;

  ()   Free GIS & Flash consultant/developer
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