Description:
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Hello,
there is a issue if you want to sort your searchresult by multivalued attributes.

ldap_sort() works fine, but only if you sort by singlevalued attributes.

Reproduce code:
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I don't post code here, because its trivial. I will post an example dataset with two entries:

entry one:
sn=aaaa
id=1111
id=2222
id=3333

entry two:
sn=bbbb
id=6666
id=1000

Expected result:
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If you sort by "id", the second entry should move to the first place, which he doesnt, because only the first vlaues of "id" got compared.



Actual result:
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entry one remains entry one, although id=6666 is greater than id=1111!
ldap_sort() overlooks, that there is an id which is smaller (id=1000).

I think the solution to this could be to tell ldap_sort() to search for the biggest value in the multivalue attribute prior comparing with the other entries.