I'm seeing some anomolous behaviour with ItemAttachmentUpdate and haven't
been able to locate any docs specifically mentioning what I'm seeing.
Just wondering if anyone else has noticed this.

Basically, I'v got an app that intercepts the ItemSend event in groupwise,
extracts some of the FILE type attachments (basically office documents, if
any), processes them, and then attempts to reattach them.

I am using ItemAttachmentUpdate to perform the reattachment and I'm
noticing that the ORDER of reattaching is VERY significant.

I was under the impression that using ItemAttachmentUpdate and specifying
an Attachment Index would simply update the attachment at that index and
preserve the index and ordering of all other attachments.

This doesn't appear to be the case though.

It appears like ItemAttachmentUpdate actually "Deletes" the attachment at
the given index, and then adds the "new" attachment to the end of the
attachment list.

Thus, if you have several attachments and attempt to "update" the first,
all the attachments subsequently get renumbered.

Is this the expected behavior?