"Copy Subtree" fails with fatal error when using SlaveServer (MySQL Master-Slave)

When using MySQL Master-Slave replication, and corresponding eZ Publish DB settings for SlaveServer, copying a subtree will fail with a fatal error.

Steps to reproduce:

1. Prepare a MySQL Master-Slave environment
2. Configure SlaveServer settings*
3. In the administration interface, copy a subtree using the contextual menu.

Result:

A transaction error will ocurr

legacy site.ini settings:

[DatabaseSettings]
...
UseSlaveServer=enabled
SlaveServerArray[]= <slave host>
SlaveServerPort[]= <etc> 
SlaverServerUser[]= <etc>
SlaverServerPassword[]= <etc>
SlaverServerDatabase[]= <etc>