creating names in plpgsql-functions

Hi,

is there a way to make a name in a plpgsql procedure dynamic? I want to
do something like this:

CREATE FUNCTION create_admin(BPCHAR)
RETURNS BPCHAR AS '
        DECLARE
                seqname name;
                a alias for $1;
        BEGIN
                insert into admin(adminid)
                values (a);

                seqname := a || ''_seq'';

                create sequence seqname;

                return seqname;
        END;'
LANGUAGE 'plpgsql';

Calling this function returns

SELECT create_admin('TS');
ERROR:  parser: parse error at or near "$1"

Thanks,

Lieven