The subversion integration with 8.x is still very limited, especially about multi users and athentication. Afaik using the Subversion package with IS you must explicelty map every IS User to a Subversion user (even if they are identically named). So I do not see a possibility to use more advanced possibilities like kerberos (although I would really prefer to have those to).
If you (or anybody else) manage to find a better way, please post it here.
#webMethods#Integration-Server-and-ESB