Wirelessly posted (8700g: BlackBerry8700/4.1.0 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/100)
Common issue with some 8100s. Check this link, look at the 8100 section and read the link about missing call logs...
http://www.blackberryfaq.com/index.php/Main_Page
Good luck.