You can try this one:

Open a file:

/engine/lib/elgglib.php

Find the line with this text:

function friendly_title($title) {

$title = trim($title);

$title = strtolower($title);

$title = preg_replace("/[^\w ]/","",$title); 

And change to this code (comment two lines):

function friendly_title($title) {

$title = trim($title);

// $title = strtolower($title);

// $title = preg_replace("/[^\w ]/","",$title); 

It seems it will help you. :)

Hello!! Pavel M

The modification show accent in character the url, I need show characters without accent in the url.

Exemple:

My URL : http://mysite.com/ícone-coração-táxi

Change to : http://mysite.com/icone-coracao-taxi

Sorry Marco, :)

You can use this lines without comments:

$title = strtolower($title);

$title = preg_replace("/[^\w ]/","",$title);

You need to include after this rows news lines (function friendly_title):

$title = str_replace("ç","c",$title);

$title = str_replace("ã","a",$title);

$title = str_replace("á","a",$title);

etc. 

i.e.    $title = str_replace("symbol_what_you_have","symbol_what_you_need",$title);

...new lines... It's my mistake.