ps2pdf versus pstill and password protection of pdf documents

While reading about ps2pdf (which is just a commandline front-end to ghostscript), I realized that despite its simple appearance, ps2pdf has almost all capabilities of Acrobat 5. ps2pdf14 outputs Acrobat 5-compatible files. According to the documentation strong password protection should be possible, however, I never managed with that.

In theory the following commands should work:

-sOwnerPassword= and -sUserPassword=

In order to set the key length to 128 you have to use
ps2pdf14 -dEncryptionR=3 -dKeylength=128

Adobe Acrobat 5.0.5 under wine

I reinstalled Acrobat 5 to run it under wine. It didn't work. The reason appeared to be again a plugin: DocBox.api. After removing it everything went smoothly. Already before (using RedHat 9) I have had trouble with a Acrobat plugin (it was WebPDF.api at that time). Most manipulation of pdf files can be easily done with Linux tools, but one thing is tricky: cropping already existing pdf files. That's why I need Acrobat.