I am not sure if I should add an issue here or somewhere else.
I have installed PDF-AS 4.1.0 on Linux:
rt-test:~# java -version
java version "1.8.0_121"
Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)
rt-test:~# uname -a
Linux rt-test 3.16.0-4-amd64 #1 SMP Debian 3.16.39-1+deb8u2 (2017-03-07) x86_64 GNU/Linux
I can sign a PDF with Handysignatur successfully. The Issue I see is that when the Filename has spaces or umlauts in it, the presented PDF to Download has the Name only until the first space or umlaut.