We're working with bp-wiki 1.02.
When creating a wiki page and trying to add a link to another wiki page (or any other wordpress/buddypress link within the site) the URL is rewritten to a non-functioning link. Links to external/3rd party sites are not rewritten.
I've tested this on the Author's website as well and can reproduce the issue.
On http://namoo.co.uk I edit a wiki page and add a link to:
The URL is rewritten to http://namoo.co.uk/groups/wiki-test-group/wiki/introduction-to-bp-wiki
...which is not valid and does not resolve correctly (note: ../../../undefinded)