<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div><blockquote type="cite" class=""><div class=""><p class="">Isn't the IMEI in stored on the phone's SIM card? That was my impression.</p></div></blockquote></div>Oh, and BTW, the serial number portion of an IMEI is only 6 decimal digits long. The rest of the IMEI identifies maker and model, possibly a software version number, and a checksum. Those parts are easily determined in typical attack scenarios. Not to mention that IMEI's aren't treated as particularly confidential anyway.<div class=""><br class=""></div><div class="">Basing anything cryptographic on the IMEI would be a really bad idea.</div><div class=""><br class=""></div><div class=""><div class=""> -- Jerry</div></div><div class=""><br class=""></div></body></html>