Change webserver from apache to nginx_apache in Evolution... Where is ./build nginx_apache?

[BBM]

When I change the webserver from Apache to nginx_apache in Evolution ( server.domain.com:2222/evo/admin/custombuild/edit-options )
... and click Save;
I don't see the "build nginx_apache"-option anywhere at /server.domain.com:2222/evo/admin/custombuild/build-software.
Is it missing (bug?), or am I missing something