Wedding bells for Nicole and Joel?

Are Nicole Richie and Joel Madden engaged? After a late performance last night with Good Charlotte in Arlington, Va., Madden was walking offstage when a radio deejay announced to the crowd, "He got engaged yesterday! Congratulations, Joel!" Madden quickly glanced back over his shoulder but was otherwise unresponsive. "We heard this morning," the radio host told People mag. Saying he got the news from "good sources," the deejay said he'd offered congrats to Madden earlier in the night. "He said, 'Thank you so much.' They're very excited about the baby and the wedding. They want to keep their personal life personal."