So, the problem is that, when one calls run-scheme, a new buffer for scheme interaction is opened, with major mode scheme-interaction-mode. So far so good, except that scheme-interaction-mode (defined in xscheme) calls not only its hooks (as it should), but also scheme-mode's. That causes Geiser to try to activate geiser-mode in that buffer, and since it's not able to guess what's the implementation for that scheme buffer, it asks you. If you just press return there, you'll see you end up in xscheme's interaction buffer.
I've pushed a patch to the git repos that workarounds this problem (imho, this is actually a bug in xscheme, but it's easy to "fix" it on our side), by checking that we're in scheme-mode before turning on geiser-mode. I'm hoping i'll find a bit of time during the following days for a new release. Thanks for your time investigating the issue! Cheers, jao -- To achieve great things, two things are needed: a plan, and not quite enough time. -- Leonard Bernstein
