Exhibit 99.1 - Explanation of Responses
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(1) As described in the Schedule 13D (the "13D") filed with the Securities and
Exchange Commission by the Reporting Persons on March 7, 2007 with respect to
the Issuer's securities, OppenheimerFunds, Inc. ("Oppenheimer"), D. E. Shaw
Valence Portfolios, L.L.C. ("Shaw") and Tudor Investment Corporation (together
with Oppenheimer and Shaw, the "Non-Affiliated Funds") and S.A.C. Capital
Management, LLC ("SAC Management") entered into an agreement as of March 4, 2007
(the "Agreement"), which agreement is more fully described in the 13D. By reason
of the execution of the Agreement, SAC Management and the Non-Affiliated Funds
may be deemed to be members of a group within the meaning of Rule 13d-5(b)
promulgated under the Securities Exchange Act of 1934, as amended, with regard
to their respective interests in equity securities of the Issuer. The amount of
the Issuer's securities held by the Reporting Persons as reported herein does
not include the holdings of any of the Non-Affiliated Funds and each of the
Reporting Persons disclaim any pecuniary interest in the Issuer's securities
held by the Non-Affiliated Funds.

(2) S.A.C. Capital Associates, LLC ("SAC Capital Associates"), S.A.C. Meridian
Fund, LLC ("SAC Meridian"), S.A.C. Select Fund, LLC ("SAC Select"), Sigma
Capital Associates, LLC ("Sigma Capital Associates") and CR Intrinsic
Investments, LLC ("CR Intrinsic Investments"), each an Anguillan limited
liability company, each directly own Common Stock of the Issuer. S.A.C. Capital
Advisors, LLC, ("SAC Advisors") and SAC Management are investment managers to
SAC Capital Associates, SAC Meridian and SAC Select; Sigma Capital Management,
LLC ("Sigma Management") is investment manager to Sigma Capital Associates; and
CR Intrinsic Investors, LLC ("CR Intrinsic Investors") is investment manager to
CR Intrinsic Investments.

(3) Pursuant to investment management agreements, (i) each of SAC Advisors and
SAC Management share all investment and voting power with respect to the
securities held by each of SAC Capital Associates, SAC Meridian and SAC Select,
(ii) Sigma Management maintains investment and voting power with respect to the
securities held by Sigma Capital Associates and (iii) CR Intrinsic Investors
maintains investment and voting power with respect to the securities held by CR
Intrinsic Investments. Steven A. Cohen controls each of SAC Advisors, SAC
Management, CR Intrinsic Investors, and Sigma Management. CR Intrinsic
Investments is a wholly owned subsidiary of SAC Capital Associates. In
accordance with Instruction 5(b)(iv), the entire amount of the Issuer's
securities held by SAC Capital Associates, SAC Meridian, SAC Select, Sigma
Capital Associates and CR Intrinsic Investments is reported herein. The
Reporting Persons disclaim any beneficial ownership of any of the Issuer's
securities to which this report relates for purposes of Section 16 of the
Securities Exchange Act of 1934, as amended, except to the extent of its
indirect pecuniary interest therein, and this report shall not be deemed an
admission that any Reporting Person is the beneficial owner of such securities
for purposes of Section 16 or for any other purposes.