TO 'MYISAM_SORT_BUFFER_SIZE'
Problem: 'myisam_sort_buffer_size' is a parameter used by 
mysqld program only whereas 'sort_buffer_size' is used by
mysqld and myisamchk programs. But the error message printed
when myisamchk program is run with insufficient buffer size 
is myisam_sort_buffer_size is too small which may mislead to the
server parameter myisam_sort_buffer_size.
SOLUTION: A parameter 'myisam_sort_buffer_size' is added as an
alias for 'sort_buffer_size' and the 'sort_buffer_size' parameter
is marked as deprecated. So myisamchk also has both the parameters
with the same role.