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Veeam backups with snapshots

How does Veeam Backup and Replication 5.0 behave with existing VMware snapshots, or snap operations that happen during a backup? These are the results of my tests, which in general show that Veeam and the snapshots behave well and as you would assume them to, with one notable exception:

(These tests were performed with Veeam 5.0.2.230 64 bit against a VMware ESX 4.1 Update 1 patch level 348481 host with vCenter 4.1 Update 1 patch level 345043)

What if I have an existing VM snapshot (Snap1) before the Veeam backup starts?
Veeam will take an additional snapshot (Snap2), lock the disk file from Snap1, stream data from that file plus the base disk, then commit (delete) Snap2 when the backup is complete.

What if I have several VM snapshots open?
Same behavior, all "parent" snapshot files are locked while the backup is operating.

What if I try to commit (delete) my snapshot (Snap1) while Veeam is running?
VMware will throw the error "Unable to access file since it is locked". Then the "Snap1" snapshot will disappear from Snapshot Manager, but it's still there on the disk! Bad! However, the operation to commit that snapshot must be queued somewhere, for when Veeam finishes its backup run, it will not only commit its snap "Snap2", but "Snap1" will also commit as soon as Veeam releases its lock on the file. If anyone has information about this "queued-commit" behavior, I'd love to hear it.

Is Veeam doing a "Delete All" then?
No. If you have additional previous or later snapshots in the tree, they will still exist when Veeam is done.

So...can I take three snapshots, start a Veeam backup (creating a fourth snapshot), then delete snap #2?!...
Yes. You'll get the lockfile error and snap #2 will disappear from the list, and when Veeam is done snaps #4 and #2 will commit, leaving snaps #1 and #3.

Can I take a snapshot while Veeam is performing a backup?
Yes. Veeam will not touch your snapshots. As stated above, it doesn't do a "Delete All", it only commits the snapshot that it took.

If you have an existing snapshot when Veeam starts a backup, does it force Veeam to take a full backup?
No. Veeam happily performs an incremental backup.

Final notes: We've had various problems with Quest (Vizioncore) vRanger's behaviors surrounding snapshots in the past few years, to where we always suspended vRanger when we had snaps open. It's good to see that Veeam handles snaps gracefully. Current versions of vRanger may have improved snapshot behavior; I probably won't have an opportunity to test.