Bonjour,
Déjà désoler du retard, je n'avais pas vu la réponse …
Donc nouveau test avec les parameter que je peu mettre en utf8 et même erreur et même problème :
1/ Sur Windows
mysql> SHOW VARIABLES LIKE 'character_set%';
+————————–+———————————–+
| Variable_name            | Value                             |
+————————–+———————————–+
| character_set_client     | utf8                              |
| character_set_connection | utf8                              |
| character_set_database   | utf8                              |
| character_set_filesystem | binary                            |
| character_set_results    | utf8                              |
| character_set_server     | utf8                              |
| character_set_system     | utf8                              |
| character_sets_dir       | C:\Alfresco\mysql\share\charsets\ |
+————————–+———————————–+
8 rows in set (0.00 sec)
commande d'export : mysqldump -u root alfresco –single-transaction > C:\sauvegardes_Alfresco\sauvegarde\MySQL\alfresco_hot.sql
2/ sur Ubuntu
mysql> SHOW VARIABLES LIKE 'character_set%';
+————————–+—————————-+
| Variable_name            | Value                      |
+————————–+—————————-+
| character_set_client     | latin1                     |
| character_set_connection | latin1                     |
| character_set_database   | latin1                     |
| character_set_filesystem | binary                     |
| character_set_results    | latin1                     |
| character_set_server     | latin1                     |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+————————–+—————————-+
8 rows in set (0.00 sec)
3/Je rajoute dans le my;cnf :
#Set the default character set
default-character-set=utf8
#Set the default collation
default-collation=utf8_general_ci
Ce qui me donne :
mysql> SHOW VARIABLES LIKE 'character_set%';
+————————–+—————————-+
| Variable_name            | Value                      |
+————————–+—————————-+
| character_set_client     | latin1                     |
| character_set_connection | latin1                     |
| character_set_database   | utf8                       |
| character_set_filesystem | binary                     |
| character_set_results    | latin1                     |
| character_set_server     | utf8                       |
| character_set_system     | utf8                       |
| character_sets_dir       | /usr/share/mysql/charsets/ |
+————————–+—————————-+
8 rows in set (0.00 sec)
ensuite :
mysql -u alfresco -palfresco -e "drop database alfresco;"
mysql -u alfresco -palfresco -e "create database alfresco;"
mysql -u alfresco -palfresco alfresco <alfresco_hot.sql
enfin :
Je recopie le alf_data
, je relance et ca ne marche pas avec l'erreur dans alfresco.log : 
 ERROR [org.alfresco.repo.domain.schema.SchemaBootstrap] Statement execution failed:
   SQL: alter table JBPM_ACTION add index FK_ACTION_REFACT (REFERENCEDACTION_), add constraint FK_ACTION_REFACT foreign key (REFERENCEDACTION_) references JBPM_ACTION (ID_)
   Error: Can't create table 'alfresco.#sql-334_29' (errno: 121)
   File: /opt/alfresco-3.4.d/tomcat/temp/Alfresco/AlfrescoSchema-MySQLInnoDBDialect-Update-218997635113435688.sql
   Line: 29
——————————————————————————–
Par contre en reprenant mes test, le "Workaround" ne fonctionne plus .. a savoir qu'après une sync ladap-ad, j'ai de nouveau perdu tous les proprietaires de sites …