Comment 2 for bug 1384237

After investigating a little bit more, it appears it is caused by the inability of the upgrade script to upgrade PostgreSQL

From main.log :
2014-10-22 14:40:05,871 DEBUG blacklist expr '^postgresql-.*[0-9]\.[0-9].*' matches 'postgresql-9.1-pgmemcache'
2014-10-22 14:40:05,871 DEBUG The package 'postgresql-9.1-pgmemcache' is marked for removal but it's in the removal blacklist
2014-10-22 14:40:05,885 ERROR Dist-upgrade failed: 'Le paquet « postgresql-9.1-pgmemcache » est marqué pour suppression mais il est dans la liste noire des suppressions.'