[g77] D format specifier

[Athol Kemball]

I have had problems with the double precision format specifier Dw.d in g77. 
The output
contains exponent letter 'E' instead of 'D'. Tested only 3.2.1 & 2.95.3, 
but both used 'E'.
Is this expected, or does the the standard require 'D''.
Thanks.