Animate() of ScrollTop and ScrollLeft doesn't move smoothly

Animate() of ScrollTop and ScrollLeft doesn't move smoothly

Hi everybody. I have a page with a big (4000x2000) background width hidden scrollbars. There is some absolute positioned images on it. I want my navigation will be like an "fly" over page, but in IE (even 8 version) this animation doesn't work as i expect.
Here is example of code, that i use for that:
  1. $("html:not(:animated)"+( ! $.browser.opera ? ",body:not(:animated)" : "")).animate({scrollTop: tempbottom+'px',scrollLeft: templeft+'px'}, 3000);
The page, where problem is http://vintage.skulditsky.kz/
I also tried to use ScrollTo, UI override of Animate (by setting easing), LocalScroll, change default hardcoded timer value from 13ms to another value.
Could anyone help with this problem?