Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We hereby consent to the incorporation by reference in the Registration Statement on Form S-3 (Nos. 333-106378 and 333-107163) and Form S-8 (Nos. 333-45954, 333-45956, 333-55614, 333-55946 and 333-103475) of Avaya Inc. of our report dated December 13, 2005 relating to the financial statements, management’s assessment of the effectiveness of internal control over financial reporting and the effectiveness of internal control over financial reporting, which appears in the Annual Report to Shareholders, which is incorporated in this Annual Report on Form 10-K.

/s/ PricewaterhouseCoopers LLP

Florham Park, NJ

December 13, 2005

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