I cannot get the exclude feature to work.

I have lots of lines starting with a digit. I do not want to see them in the beaver output.

So I configure

[beaver]
format: raw 
logstash_version: 1

; * Yate logfile eplus live
[/var/log/apache2/access.log]
exclude: ^[0-9]

This still ships every line.

The only "regex" I found to "work" was:

exclude: .

which, as expected, excluded all lines.

Every other type of regex I tried did not match.

exclude: ^[0-9]
exclude: (^[0-9])
exclude: ^([0-9])
exclude: "^[0-9]"
exclude: "(^[0-9])"
exclude: "^([0-9])"
; desperate try: match only lines starting with 2
exclude: ^2

I tried beaver 33.0, 33.1 and then upgraded to 36.2.0 which behaves the same.

python is python2.7.3-6 on debian wheezy
I also tested
python 2.7.9-2 on debian jessie
which shows the same behaviour.