Prosecutor-General Qorbanali Dori-Najafabadi reportedly said Jahanbegloo admitted to plotting a "velvet revolution" and apologized for his "mistakes."
Jahanbegloo was detained on April 27 on unspecified security charges. Friends and colleagues have said they fear he could be under pressure to make forced confessions.
Rights groups both inside and outside Iran have called for Jahanbegloo's release.
A Canadian-Iranian philosopher educated in France and the United States, Jahanbegloo has written about and lectured on democracy in Iran.
More recently, he challenged President Mahmud Ahmadinejad's denial of the Holocaust.
(www.kargozaraan.com)