We have some problem during update propagations to external resource of users and roles in Syncope 1.2.1.
In our case, the external resource has a derived attribute configured as account id.
During the propagation task it seems that syncope performs a getRemoteObject operation (in AbstractPropagationTaskExecutor) passing username/rolename attribute instead of the designed account id attribute (internal attribute specified in user/role mapping configuration).
Here you can find a patch create with Francesco's collaboration:
Relevant e-mail thread: http://markmail.org/message/dlrtnh7phzechdy4