Multiple plugin execution sections not correctly executed

I have a JAR project that is using the dependency:unpack-dependencies to package all dependencies into one big applet JAR.
This applet JAR also needs to be signed. I have another JAR containing the JKS for this (via keytool-maven-plugin).
What I want to do now is to first unpack the JKS JAR into target/keystore (generate-sources phase) and then to also unpack all the other dependencies except the JKS JAR into target/classes (generate-resources phase).
And afterwards to sign via maven-jar-plugin using the JKS from target/keystore (package phase).
For this I use two execution sections within the maven-dependency-plugin section.
And this is where the maven-dependency-plugin completely fails if you give each execution section its own configuration.