Malte-
You mention that you have integration working? Was this some super customized effort? How would I duplicate your results if I wanted to?
The reason I ask, is that there are a bunch of mature OSS products that would be greate to integrate into OACS without having to rewrite them. Would the appropriate strategy be to do a default install of a webmail program, IMP for example, and then install an OACS package that is the "IMP integration" package?
Or is this impossible due to changes required in IMP?
The goal I have in mind is not to prove integration possible, which it clearly is, but to make integration as close to plug and play as possible.