Conflict with Synchronize translation module

This issue was driving me insane. Every time that a user removed a node from the front page, its translation would be promoted. This made it impossible to remove both nodes from the front page. Changing the synchronization settings did not solve the problem.

What did finally work was for me to change the default value of the Promoted to front page option for that node type. I think what is happening is that the synchronization module is causing hook_nodeapi() to be run for both nodes, and this module applies the default options to the translation.