Illinois Supreme Court Rule 216 governs requests to admit. A new version of Rule 216 took effect on January 1, 2011. There are two new requirements in the amended Rule 216.
First, the maximum number of requests to admit that a party may serve on another party has been limited to 30, unless the parties agree otherwise or upon court order. If a request contains subparts, each subpart counts as a separate request.
Also, a party must (1) prepare a separate paper which contains only the requests to admit; (2) serve the paper separate from other papers; and (3) put the following warning in a prominent place on the first page in 12-point or larger boldface type: "WARNING: If you fail to serve the response required by Rule 216 within 28 days after you are served with this paper, all the facts set forth in the requests will be deemed true and all the documents described in the requests will be deemed genuine."
Requests to admit can have drastic consequences for parties that fail to answer, or answer incorrectly. Now there are also strict requirements on the propounding party as well.
Be sure to update any forms accordingly. It would be a shame if the responding party blew their deadlines, but you could not get the facts admitted because you were using last year's forms.