[Exist-open] Value index gets broken after XUpdate

[<sju...@ko...>]

Hello,

I'm running into a bug in the value indexing. After issuing an XUpdate 
on an attribute, the declared value index on that attribute is only 
partially used:

- no statement that the value index was used is given
- all subsequent attribute nodes with the same name is traversed, in 
what looks to me like default collation order (all is printed to the 
console)

I have to recreate the index on the collection to get back to the value 
index-based lookup properly.

The update looks like the following:

<xupdate:update
   select="doc('/db/ordbase/terms/SD-terms/terms-sme.xml')//entry/@id[. 
= 'vuoivvas\S']">vuoivvi\S</xupdate:update>

Regards,
Sjur