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

Another thing that I don't know how to handle easily with ps2pdf is the cropping of documents.

For the password protection, a very good alternative seems to be PStill (http://www.pstill.com/). The command:

pstill -Muserpassword=testpassword testfile.ps

does the trick.