First you need to build some things from ThirdParty which SOPE is based on.

Note: ThirdParty in this case doesn't mean that you need to fetch the sources of those libraries and tools yourself. Stable - and sometimes patched - versions of the required sources are contained in the ThirdParty Subversion repository.

You find the information on how to build ThirdParty packages required on the SOPE website.

After you have finished building the basic things from ThirdParty required, you can go on building the core application server, SOPE.