Exhibit 99.2
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                                Power of Attorney

KNOW ALL MEN BY THESE PRESENTS, that I, STANLEY F. DRUCKENMILLER, hereby make,
constitute and appoint each of Gerald Kerner and Joseph W. Haleski acting
individually and with full power of substitution, as my agent and
attorney-in-fact for the purpose of executing in my name, (a) in my personal
capacity, (b) in my capacity as managing member or in other capacities with
Duquesne Capital Management, L.L.C., a Pennsylvania limited liability company
("Duquesne Capital") or (c) in my capacity as managing member or in other
capacities of Duquesne Holdings, LLC, a limited liability company organized
under the laws of Anguilla, British West Indies ("Duquesne Holdings"), and each
of their affiliates or entities advised or controlled by me, Duquesne Capital or
Duquesne Holdings, all documents, certificates, instruments, statements, filings
and agreements ("documents") to be filed with or delivered to any foreign or
domestic governmental or regulatory body or required or requested by any other
person or entity pursuant to any legal or regulatory requirement relating to the
acquisition, ownership, management or disposition of securities or other
investments, and any other documents relating or ancillary thereto, including
but not limited to, all documents relating to filings with the United States
Securities and Exchange Commission (the "Commission") pursuant to the Securities
Act of 1933, as amended, or the Securities Exchange Act of 1934 (the "Exchange
Act") and the rules and regulations promulgated thereunder, including: (1) all
documents relating to the beneficial ownership of securities required to be
filed with the Commission pursuant to Section 13(d) or Section 16(a) of the
Exchange Act including, without limitation: (a) any acquisition statements on
Schedule 13D or Schedule 13G and any amendments thereto, (b) any joint filing
agreements pursuant to Rule 13d-1(k), and (c) any initial statements of, or
statements of changes in, beneficial ownership of securities on Form 3, Form 4
or Form 5 and (2) any information statements on Form 13F required to be filed
with the Commission pursuant to Section 13(f) of the Exchange Act. All past acts
of the attorney-in-fact in furtherance of the foregoing are hereby ratified and
confirmed. This power of attorney shall be valid from the date hereof until
revoked by me.

IN WITNESS WHEREOF, I have executed this instrument as of the 24th day of April,
2002.


/s/ Stanley F. Druckenmiller
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Stanley F. Druckenmiller