R12: Expense Reports get stuck after approval

Today I got to deal with a new A/P issue that we've reported to Oracle development, where APEXP workflows will spawn off the AME approval process successfully but after approval the workflow doesn't report back to the parent workflow.  Instead of having the child process report back, the parent workflow sits there at the Block stage until you retry the most recent Active stage which was the AP Approval Process and then the parent workflow goes all the way to the end allowing the invoice to be imported and paid.  We're not sure why certain expense reports fail in this way, as most succeed without issue, but I wanted to put this out there so you can try the workaround and I'll follow up with what we find as a resolution or cause.