Issue activating plugin

Hello,

I have been migrating a WordPress installation. When I try to activate this geotargeting plugin (http://webous.com/products/wordpress-geotargeting/) from the administration panel, I get the following:

The plugin generated 1718 characters of unexpected output during activation. If you notice “headers already sent” messages, problems with syndication feeds or other issues, try deactivating or removing this plugin.

I am receiving this error when I visit the home page after activating the plugin:

Fatal error: Unknown: Cannot use output buffering in output buffering display handlers in Unknown on line 0

Nothing appears on the page besides this. I have deactivated any plugins I don’t need, and this is definitely the one causing the problem.

I have tried contacting the developer regarding the problem.

1. Is there any other plugin that can drop in with the current syntax and work?
2. What can I do to continue to debug this?

Thank you