Problem with language selector

Site https://www.katherinejewelry.com
It has been working for about two years now, and it worked well.
But...
A few days ago admin couldn't log in.
Server host has updated php to 2.5.11 version, and I fixed that problem with general.php following advice at http://www.zen-cart.com/forum/showthread.php?t=137855

In Firefox and IE , everythings looks OK now, but in Google Chrome, I have following message at the bottom on the page:

Fatal error: Class 'queryFactory' not found in /home/cvrbush/public_html/includes/functions/sessions.php on line 54

and...
I have specific issue with langugage. When I select serbian language, and then a category from the category tab, it takes me back to the default langugage which is english.

I don't know if those two problems are related with servers php configuration ( as I believe because everything was just fine until host didn't update php ) or.. some problem with zen-cart.

Zen-Cart = 1.3.8
Installed mods:

• Built in Multilanguage EZ pages for English and Serbian language
• Built in Serbian language pack
• Fual lightbox
• IH2
• Gallery mod ( to present sold or not for sale artworks )
• Language and Curency header mod

Any suggestion please !