Illegal mix of collations (cp1251_general_ci,IMPLICIT), (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'between'

SET CHARACTER SET koi8r;

set names koi8r;

create table t1 (c1 char(10) character set cp1251);

insert into t1 values ('ß');

select c1 from t1 where c1 between 'ß' and 'ß';

drop table t1;

mysqltest: At line 6: query 'select c1 from t1 where c1 between 'ß' and 'ß'' failed: 1270: Illegal mix of collations (cp1251_general_ci,IMPLICIT), (latin1_swedish_ci,COERCIBLE), (latin1_swedish_ci,COERCIBLE) for operation 'between'