There's no tool that meets my expectations or it is too complex for my needs. Today I found this great WinZip add-on (thx nrg!). The following commands placed in a common batch file do the trick:

del e:\backup.zip
svnadmin dump e:\_data\qlzrep01 > C:\svndump
wzzip -s -ycAES256 -r -P -ee -x@"C:\_backupexclude.txt" e:\backup.zip @"C:\_backuplist.txt"

-s: asks for a password
-yc: encryption algorythm
-r: recursive mode
-P: store full paths
-ee: enhanced deflate method
-x@: list of files (wildcards) to exclude
@: list of files to add to the archive

c:\_backuplist.txt
"C:\_backup.bat"
"C:\_backuplist.txt"
"C:\svndump"
"C:\Documents and Settings\x\Application Data\Mozilla\Firefox\*.*"
"C:\Documents and Settings\x\Application Data\Thunderbird\*.*"
"C:\htdocs\*.*"
... etc ...

c:\_backupexclude.txt
; music videos
"E:\_hobby\(media files)\*.*"
; dj mixes
"E:\_hobby\djmix\*.*"

Works perfectly. There's no better tool for Windows if you have a well-structured directory tree.