On the support website a kb-article describes how you can configure the iwwebd so that it rotates it logs using the apache rotatelogs utility. Unfortunately the kb-article does not seem to be correct on a windows environment.
Following the kb you must modify the line about customlogs in iwwebd.conf.template to something like this:
[PHP]CustomLog "| path_to_iwhome/iw-webd/bin/rotatelogs __IWWEBD_LOGS__/access__IWLOG_EXT__ 86400" common[/PHP]
During a iwreset the placeholders will then be replaced by the proper path and extension. However on windows the path will contain \-characters and these seem to break the rotate utility.
If instead of using '__IWWEBD_LOGS__' you use the hardcoded path with /-characters like 'd:/interwoven/teamsite' your logs will rotate.
Also more info on the rotatelogs utility on the apache docs:
http://httpd.apache.org/docs/2.2/programs/rotatelogs.html
