POA DOCUMENT

KNOW ALL BY THESE PRESENTS, that I, FRANK H. PEARL, hereby make, constitute and
appoint each of KENNETH M. SOCHA and TERESA Y. BERNSTEIN, each of them acting
singly, as my agent and attorney-in-fact for the purpose of executing in my
name, (a) in my personal capacity or (b) in my capacity as Chairman of, member
of or in other capacities with Perseus, L.L.C. ("Perseus") and each of its
affiliates, or entities advised by me or Perseus, 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, futures contracts, or other investments, and any
other documents relating or ancillary thereto, including, but not limited to,
all documents relating to filings with the Commodities Futures Trading
Commission and National Futures Association, the United States Securities and
Exchange Commission (the "SEC") pursuant to the Commodities Exchange Act and the
Securities Act of 1933 or the Securities Exchange Act of 1934 (the "Act") and
the rules and regulations promulgated thereunder, including all documents
relating to the beneficial ownership of securities required to be filed with the
SEC pursuant to Section 13(d) or Section 16(a) of the Act and information
statements on Form 13F required to be filed with the SEC pursuant to Section
13(f) of the Act.

All past acts of either 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.

The Power of Attorney dated as of May 9, 2007 is hereby revoked by me effective
as of the date hereof.

IN WITNESS WHEREOF, I have executed this instrument as of the 6th day of
December, 2007.


/s/ Frank H. Pearl
Frank H. Pearl