As a title said, i make ftf file for relocking bootloader for Sony XPERIA T.I can confirm, that it work, try checking via Emma (Sony service program) and also via Sony Update Service and all ok. Just flash provided ftf file via flashtool and than you hawe locked bootloader. Waiting for some new kernels here...
source - www.XPERIA.cz
download - https://rapidshare.com/files/3381794...Bootloader.ftf
source - www.XPERIA.cz
download - https://rapidshare.com/files/3381794...Bootloader.ftf