On bug 30996, Tim recommended changing the collation method to "uca-default" on a language-by-language basis, after checking each language for correct collation and first-letter behaviour on a test wiki.
According to the tests made by Bawolff, the "uca-default" collation method seems to work fine on Portuguese:
http://thread.gmane.org/gmane.science.linguistics.wikipedia.technical/59758/focus=59767
and in the same topic, Tim said the results are good enough.
On
[[pt:Wikipédia:Esplanada/propostas/Melhorar a ordenação das páginas com títulos acentuados (20mar2012)]]
editors from Portuguese Wikipedia agreed to enabling uca-default sorting on ptwiki.
So, I believe it is feasible to set $wgCategoryCollation to 'uca-default' on ptwiki (and make any necessary updates, or run the necessary maintenance scripts).
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**Version**: unspecified
**Severity**: enhancement
**URL**: https://pt.wikipedia.org/wiki/Wikip%C3%A9dia:Esplanada/propostas/Melhorar_a_ordena%C3%A7%C3%A3o_das_p%C3%A1ginas_com_t%C3%ADtulos_acentuados_%2820mar2012%29
**See Also**:
https://bugzilla.wikimedia.org/show_bug.cgi?id=30996
https://bugzilla.wikimedia.org/show_bug.cgi?id=45911