I try to use procmail in my user directory on a server to filter my mail. Procmail is called from .forward in my home directory.
However, it seems that sendmail ignores .forward and mails are not passed through procmail (the local mailer is mail).
I suspect know, what causes my problem: my home directory is not given in the
forward_path option in sendmail.cf, or an other forward path takes precedence there.
If so, I may dare to include $z/.forward there (I know the su password).
However, I am afraid that I make a mess in the config file if I edit it directly (and block the mails of 50 other users), as I read somewhere that the .cf files are compiled from *.mc files by m4.
So, can I directly edit sendmail.cf to add a new forward_path?
Should I stop sendmail meanwhile (or after) and restart it so that the new configuration be effected?
Do I have to specify procmail as a feature or mailer, even if it is called explicitly from .forward? (I'd rather avoid that, if possible).
Please help me!

There was no problem with sendmail.
It was a great experience: when editing unix config files from a remote Windows machine, one should rather struggle with ssh and vi than edit them with Wordpad through a network share...
I suspected this from the beginning, but was misleaded by some error messages.