Exhibit 10.1

                CONSENT OF ERNST & YOUNG, INDEPENDENT AUDITORS

   We consent to the reference to our firm under the caption "Selected
Financial Data" in this Annual Report (Form 20-F) for the year ended December
31, 2001, and to the incorporation by reference in the Registration Statement
on Form F-3 (File No. 333-13802) and Registration Statements on Form S-8 (File
Nos. 333-06850, 333-11384, 333-12326, 333-13224, 333-13330 and 333-13494)
pertaining to the Executive Share Option Scheme, the 1997 Share Option Scheme,
as amended, the 1997 Director Share Option Scheme and the 1999 Employee Stock
Purchase Plan of IONA Technologies PLC, the 1997 Stock Plan of Genesis
Development Corporation, the Stock Plan of Object-Oriented Concepts, Inc. and
the 1999 Stock Option Plan of Netfish Technologies, Inc., of our report dated
January 22, 2002, with respect to the consolidated financial statements of IONA
Technologies PLC included in this Annual Report (Form 20-F) for the year ended
December 31, 2001.

                                          ERNST & YOUNG

Dublin, Ireland
May 31, 2002