Wirelessly posted (HTC Touch Pro 2: Mozilla/4.0 (compatible; MSIE 6.0; Windows CE; IEMobile 8.12; MSIEMobile6.0) Sprint T7380)

im presently using what i thought was a great app for locking the screen called pocketshield...it was made for another phone but the tp2 took it well...i noticed every now and then i had this screen would come up and start counting seconds, down from ten, nine, and on ...i was locked out for that time...turns out..i had a demo and this was its programming...felt like a virus though...anyways...does anyone know of a good screenlock thats free...i wanted to know before i buy one...thanks