The error you cite is not being reported by SQL Anywhere or its components. Can you debug to get the error reported from the sync call. I suspect that the error is -1305. The error message would be MobiLink communication error -- code: %1, parameter: %2, system code: %3 where %1, %2, and %3 will be replaced with context for the cause of the error. That context would help figure out this issue.
As a starting point, this appears to simply be a connectivity issue. Can you ensure that you can ping the host machine where the MobiLink server is running?.