92 Ill. Adm. Code 450.350
Appearance
Section 450
Section 450.350 Appearance
A respondent may participate in
the proceedings without forfeiting any jurisdictional objection, if such
objection is raised at or before the time the respondent files his initial
pleading or motion, or, if no pleading or motion is made, before the commencement
of a hearing; otherwise appearance either for purposes of motions or otherwise
pleading shall subject the respondent to the full jurisdiction of the hearing
officer.