TCP guarantees packet delivery.
For sure: just received this update now...
------------ Thank you for your order you placed on 2009-08-11.
This is an automated notification that xyztwbooks has indicated that your recent abdcef.com order has been processed and will ship within 24-48 hours. If your order is from more than blah blah...
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BTW the project this book was for has been closed for long. Fortunately :-)