Keyboard Shortcuts don't work after scrolling on a page DELL VOSTRO 3450

I have the problems with DELL VOSTRO 3450. I have try to install latest synaptic driver from http://www.synaptics.com/en/drivers.php. However, I can't scroll on the touch pad so I install driver from http://www.dell.com/support/home/us/en/04/product-support/product/vostro-3450/drivers. Is anyone have an idea?

same issue here https://code.google.com/p/chromium/issues/detail?can=2&start=0&num=100&q=&colspec=ID%20Pri%20M%20Iteration%20ReleaseBlock%20Cr%20Status%20Owner%20Summary%20OS%20Modified&groupby=&sort=&id=351995