note 17942 rejected from function.chmod by irc-html

I try to write files to the server via php. this works fine, as long as i create the directories by ftp and set the to mod 777. if i try to do so with php it will stall, if i try to create a subdir to a php-created dir. the reason seems to be, that the mod is 755 (no matter what umask i set). maybe the dirperms are sticky in some way. how can i turn this off?? i assume its something with the numbers before 777 (something like umask 1777)???? i cannot find a simple solution. any help here?