Menu don't show submenu items

Hi, my menu don't show submenu items when deployed.
Maybe this can be because it need an update. I have the CK Accordion 1.6.1 version for joomla 2.5 and I know you have 1.9.10 for this joomla version.
If is this the problem, Can I update from 1.6.1 to 1.9.10 version normally throught joomla administrator or FTP? or I need to do something more?
And if is this not the answer, what could be happening?
Thanks, I appreciate an answer.

Hi
it should be working also with the 1.9 version
give me your url to check this
CEd

Hi
The demo site page is extranet.clinicaucsancarlos.cl:5555/qas_.../2012-06-05-17-53-52 (look at right, below, in "servicios clinicos" menu).
How can I update?
Thanks!

I have checked and I see the accordeon menu working... What is exactly the problem ?

The problem is that the sub-item are not visible. When you open the menu, should show other menu items, which are not seen. I reviewed the menu and is correct. Perhaps is the update, but tell me, how can I upgrade?

by my side the submenus are visible ... I'm checking with Firefox
then to update, install the new version over the existing one (backup your website before all)