SQL Error after update 3.6.1 - Joomla! Forum - community, help and support

steps reproduce issue

updating joomla 3.6.0 3.6.1
under extensions->manage->database can see 3 errors: warning: database not date!
table 'lfkex_menu' not have index 'idx_client_id_parent_id_alias_language'. (from file 2.5.0-2011-12-24.sql.)
table 'lfkex_redirect_links' not have index 'idx_old_url'. (from file 3.5.0-2016-03-01.sql.)
joomla! core database tables have not been converted yet utf-8 multibyte (utf8mb4).
under 'other information' :
database schema version (in #__schemas): 3.6.0-2016-06-05.
update version (in #__extensions): 3.6.1.
database driver: mysql.
94 database changes checked successfully.
156 database changes did not alter table structure , skipped. 4 . click on 'fix'

expected result

database updated
actual result

internal server error
the server encountered internal error or misconfiguration , unable complete request.
system information (as possible)

setting value

php built on linux 3.2.0-4-amd64 #1 smp debian 3.2.68-1+deb7u1 x86_64
database version 5.5.49-0+deb7u1-log
database collation utf8_general_ci
database connection collation utf8mb4_general_ci
php version 5.4.45-0+deb7u3
web server apache
webserver php interface cgi-fcgi
joomla! version joomla! 3.6.1 stable [ noether ] 2-august-2016 22:59 gmt
joomla! platform version joomla platform 13.1.0 stable [ curiosity ] 24-apr-2013 00:00 gmt

relevant php settings
setting value
safe mode off
open basedir none
display errors on
short open tags on
file uploads on
magic quotes off
register globals off
output buffering on
session save path /var/lib/php5
session auto start 0
xml enabled yes
zlib enabled yes
native zip enabled yes
disabled functions none
multibyte string (mbstring) enabled yes
iconv available yes
mcrypt enabled yes
maximum input variables 4000

sounds failed utf8mb4 conversion. check board resolution.