thank you. problem solved
mootools disabled, because template is loading MT 1.2
used link in FAQ and found JoomSEF link at the end of page, so I've modified JoomSEF component and it's working now. Only problem remaining is autocompleter window displayed in the middle of page hidden behind some elements, but this is not a big issue
//edit: Autocompleter.js > inheritWidth: false, commented out top, left. done