What does this error message mean?  Is it serious for users and what do I do about it?

“ 09:57:16 [WARN] Tried to establish rendezvous on non-OR circuit with purpose  Acting as rendevous (pending)”

This is on a Ubuntu VPS Tor exit, although exit is limited range IP4 port 80 addresses. Full 443 and others.

Exit, Fast, HSDir, Running, Stable, V2Dir, Valid

Gerry