Thank you for your post.
At this time, Bento 2.0v4 can sync with only one device. Therefore, when you sync your second device to Bento 2.0v4, Bento 2.0v4 replaces the first device with the second device.
On a side note, this is a FileMaker Pro/Server Forum. In the future, please post your question to the Bento forum at forums.filemaker.com.
Thank you, TSGal.
Could't find the Bento forum; all links took me here!