Windows 2008 Server 64

When _id is compound object then and Mongo does actual insert :

> db.coll.findAndModify({"query":

, "update": { "$inc":

}, "new": true, "upsert": true })

exception: assertion ../bson/bsonobjbuilder.h:119", but the document is created

Then when we repeat the operation it results with proper document, and "value" is incremented.

When _id is simple type everything is ok: Mongo returns document

Again, clean database and we issue then same command but "new":false everything seems fine.