i have already started to daubt myself, because there are some filter rules i keep changing all the time and they just never work. once i forgot to set it to move the matches anywhere, instead i just left "keep it in inbox" selected, another time i used the rule "From is" instad of "subject contains" and so on. and i kept working on one and the same rule all the time..
now i have figured out, that it wasn't entirely my bad at least that's how i feel about it
here's waht went wrong:
i've added a new filter rule: if From contains XY, file into folder /inbox/xy and saved it and went back to my inbox.
a mail containing XY in the subject arrived and was not filtered, because my rule was set to look in the from field, rather than in the subject.
so i went back to the rule wizard to check my rules and found the problem.
i changed the setting to Subject contains XY and saved it again.
but my filter still left all those XY mails in my inbox. i went back to the filter and saw, that it now says "Keep in Inbox" instead of "File into folder". so i changed this back to File into folder and saved it. but then again it didn't work and when going back to my rule i saw, that it now says "file into folder" but in the criteria list it changed back to "From is" instead of "Subject contains".
i must say, that when saving my changed settings, all fields where filled in appropriately, but as it seems, after pressing the OK button, they change when the form is hidden to the default value (only those i haven't changed).
so there is obviousley something wrong. i then deleted the rule and re-entered it without any mistakes and now even this rule works
this error is reproducable by doing the procedure described above. basically just add a rule, change a part of it and save it, and the unchanged part will switch back to the defaults without any notice.
oh and... i'm using M2 on FC4 and Firefox 1.0.6 on the client