I'm prototyping an Elastix system running 2.0.3 with four Yealink T28P's with 2.60 firmware. I only have four extensions setup, 2651, 2602 2603 and 2649. I'm not having any luck making the BLF functions work on any of the phones. I've tried various configurations on the phone and within Asterisk.
I've modified the /etc/asterisk/extensions_custom.conf file with this: