Please Help!

Hi!
 
Can somebody please clarify this for me...
 
 
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4.4.1 xforms:submit
 
If the attribute value is "instance", the response is parsed as XML and
the internal instance data is replaced with the result, using the same
processing as remote instance data retrieved through xlink:href, and the
xforms:initialize event is dispatched to element model. Behaviors of
other possible values for attribute replace are not defined in this
specification.
 
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What means that exactly.
 
1.      is the complete instance data replaced by the new one
OR
2.      only the instance data bound to the submitInfo (through ref or
bind)
 
many thanks
 
michael