if you get
 Fatal error: Call to undefined function curl_init() in
../modules/mod_cursvalutar.php on line 31

then your PHP has no support for curl enabled.

here are some pointers if you want to enable it :

http://www.tonyspencer.com/2003/10/22/curl-with-php-and-apache-on-windows/

enable Curl in your PHP.ini

Issue partially solved - I installed Eur Excahge Rates Factory 2.5 on host server (CURL anabled) and it is working, but there is a error message visible on the frontend:

Warning: file_put_contents(/home/mysite/public_html/cache/curs_eur/curs_19-03-2009.xml) [function.file-put-contents]: failed to open stream: Permission denied in /home/mysite/public_html/libraries/joomla/filesystem/file.php on line 297

Could you help me?

Hi again!
I've checked the permitions cache was at max; the curs_eur was on 1411 (all the permissions have only 3 numbers - i.e. 755, which is in the directotry view is visible as 0755) - I've tried to change curs_eur one but it geves me "operation not permitted".
I even tried to do that trough host tech support but at the end they told me that if I change 1411 the whole Joomla would FAIL...

The Joomla I use is 1.5.9 and what I get in fact is: the rates are visible and updated BUT on the top of the mod there are 3 rows msg about the error I've mentioned before.

What can be done to get rid of the error and the ugly msg...
Thank you in advance

i also found this
"Fatal error: Call to undefined function curl_init() in C:\xampp\htdocs\joomla\modules\mod_euroexchangerate\helper.php on line 104"
on my web

how to fix it

i'll try. thanks mate