Deletes in an updategram

I think this a bit of a long shot as it doesn't seem (according to the
documentation and just trying it out) possible but I thought I'd double
check. I've got an update happening which also includes rows on a
different table which might have been removed during the transaction
I'd therefore like to delete the rows or remove them from the
relationship (though deleting would be better).
I have something like:
<?xml version="1.0" encoding="UTF-8"?>
<ROOT>
<updg:sync xmlns:updg="urn:schemas-microsoft-com:xml-updategram"
mapping-schema="schema/person.xsd">
<updg:before>
<y0:Person xmlns:y0="pretend:URN"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:sql="urn:schemas-microsoft-com:xml-sql"
id="65654D01-35A9-4901-91DB-5618037ACE2C">
<y0:Address id="EC3831B2-83C4-46FB-A44F-57668E7ADD47"/>
<y0:Identifiers>
<y0:Identifier personID="65654D01-35A9-4901-91DB-5618037ACE2C"
id="5BD49D1F-7521-4247-9251-C195D4BEC079"/>
<y0:Identifier personID="65654D01-35A9-4901-91DB-5618037ACE2C"
id="FFC04502-1D16-4A2A-8939-F02ACFEE134E"/>
<y0:Identifier personID="65654D01-35A9-4901-91DB-5618037ACE2C"
id="868B29EF-B749-4903-B34B-FE39E4FE3D5D"/>
</y0:Identifiers>
</y0:Person>
</updg:before>
<updg:after>
<y0:Person xmlns:y0="pretend:URN"
id="65654D01-35A9-4901-91DB-5618037ACE2C">
<y0:DateOfBirth>2001-03-12</y0:DateOfBirth>
<y0:Sex>Male</y0:Sex>
<y0:Address id="EC3831B2-83C4-46FB-A44F-57668E7ADD47">
</y0:Address>
<y0:Identifiers>
<y0:Identifier id="5BD49D1F-7521-4247-9251-C195D4BEC079"
personID="65654D01-35A9-4901-91DB-5618037ACE2C">
<y0:Value>1203120135</y0:Value>
<y0:Type>Bleh</y0:Type>
</y0:Identifier>
<y0:Identifier id="FFC04502-1D16-4A2A-8939-F02ACFEE134E"
personID="65654D01-35A9-4901-91DB-5618037ACE2C">
<y0:Value>123456A</y0:Value>
<y0:Type>Foo</y0:Type>
</y0:Identifier>
</y0:Identifiers>
</y0:Patient>
</updg:after>
</updg:sync>
</ROOT>
Now what I was hoping was the three identifiers at the top would result
in the deleted identifier being removed from the database. However
instead I get a "All updategram/diffgrams nodes with siblings must have
ids, either user specified ones or mapping schema based key field id"
which I assume is as a result of an ambiguous delete operation.
It would be of great help if someone either shot this down as something
you can't do though better if there is a way to do it without trying to
work out everything that has changed and do multiple sync operations.
Thanks,
GaryNever mind!
I was being silly. I forgot to upload one of the changed schema that
had the key-fields defined and that was what was causing the problems.
After fixing that everything worked just fine.
Thanks anyway,
Gary