Originally added to the exchange module because of the edkguid.h and edkmdb.h dependencies. However, since that module requires the deprecated exchange 2003 sdk to build, I wanted to move the functionality into the mapi module. Unfortunately, I also needed to include the requisite headers.
If exchange module is also built, QueryInterface can be used with either mapi.IID_IExchangeManageStore or exchange.IID_IExchangeManageStore.
I also added all the OPENSTORE_XXXX flags in the mapi module.