Error when adding remote repository from copied dbf

If you install GemEnterprise in one dbf, then copy that dbf multiple
times and start up a stone for each copied dbf, you will receive the
error 'Remote repository #repo already exists' when you attempt to
addRepository: to more than one of the copied dbfs. This error occurs
because when GemEnterprise is installed, it calculates a unique
identifier that is used to distinguish itself among the other
repositories. If you copy a dbf after GemEnterprise installation, you
are copying the unique identifier as well.

Workaround:

Install GemEnterprise separately in each dbf.