pdf editor to simply insert notes?

[Henrique Koesjan]

I am not completely sure
Perhaps Okular can add annotation, but I don't know if it is the same
as a pdf annotation or if the other person needs to have also Okular:
http://okular.kde.org/faq.php#HowcanIannotateadocumentandsendittoafriendcollegueetc

Also pdfedit has a function:
createAnnotation([ 444.897, 476.853, 548.9522, 486.988 ], 'Widget');
I've tried several times and I was not able to add any annotations with it.

henrique