Just tried my FB-7390 International with Replace Kernel, and it is working now with 84.06.53 and sources 06.20
(in the past the AVM sources where not complete, and resulted in 'unresolved symbol' warnings. See http://www.ip-phone-forum.de/showthread.php?t=269147 )

Did some (very) minimal testing with ADSL and Internet Phone (SIP), and this works normal.

I would like to know AVM corrected the sources, or of the next thread is the reason for the working sources?
http://www.ip-phone-forum.de/showthread.php?t=287995

Code:
Firmware: 84.06.53 rev34469 
freetz-devel-14086

7390_06.20-release_kernel.tar.xz
FRITZ.Box_Fon_WLAN_7390.en-de-es-it-fr.84.06.53.image

# uname -a
Linux fritz.box 2.6.28.10 #1 Sat Feb 18 20:41:18 CET 2017 mips GNU/Linux