Mysql tables creation error for 3.0

Hi all I'm using MySQL 3.22.32 When running the sql scripts in horde, the horde_prefs needs : primary key (pref_uid, pref_scope, pref_name) but MySQL complains with: ERROR 1071: Specified key was too long. Max key length is 256 I created the table with a primary key of only pref_uid anyway to see if I could get away with this limitation, but when activating 'sql' preferences in horde, IMP just states session terminated and does not allow logins. If I create the table with primary key (pref_scope, pref_name) only MySQL does not complain. Can I reduce the size of pref_uid? is there a workaround? I would'nt like to 'upgrade' MySQL to a different version if possible... This is what 'should' be created: CREATE TABLE horde_prefs (

   pref_uid        char(255) not null,
   pref_scope      char(16) not null default '',
   pref_name       char(32) not null,
   pref_value      text null,

primary key (pref_uid, pref_scope, pref_name) );