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EXHIBIT 23.1
CONSENT OF INDEPENDENT AUDITORS
We consent to the incorporation by reference in the following Registration
Statements of Natural MicroSystems Corporation: Form S-3 (No. 333-44128) and
Form S-3 (No. 333-43196), of our report dated May 19, 2000, with respect to
the financial statements of InnoMediaLogic (IML) Inc. included in the current
report of Natural MicroSystems Corporation on Form 8-K/A dated on August 22,
2000, filed with the Securities and Exchange Commission.
We also consent to the reference to our firm under the caption "Experts" in
the Registration Statement (Form S-3 No. 333-44128) of Natural MicroSystems
Corporation and related Prospectus Supplement to Prospectus dated August 25,
2000 for the registration of 2,000,000 shares of its common stock and in the
Prospectus Supplement to Prospectus dated August 25, 2000 for the
registration of $175,000,000 of Convertible Subordinated Notes due 2005.
/s/ Ernst & Young LLP
Chartered Accountants
Montreal, Canada
May 19, 2000
