UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

GenCorp Inc.

(Name of Issuer)

Common Stock, $0.10 par value per share

(Title of Class of Securities)

368682100

(CUSIP Number)

December 21, 2007

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

¨ Rule 13d-1(b)

x Rule 13d-1(c)

¨ Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Page 1 of 11

CUSIP No. 368682100

1.	Names of Reporting Persons. QVT Financial LP I.R.S. Identification Nos. of above persons (entities only).             11-3694008
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a)  ¨ (b)  x
3.	SEC Use Only
4.	Citizenship or Place of Organization             Delaware

Number of   Shares   Beneficially   Owned by   Each   Reporting   Person   With:	5.    Sole Voting Power                 0
	6.    Shared Voting Power                 3,635,024
	7.    Sole Dispositive Power                 0
	8.    Shared Dispositive Power                 3,635,024

9.	Aggregate Amount Beneficially Owned by Each Reporting Person             3,635,024
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)	¨
11.	Percent of Class Represented by Amount in Row (9)             6.38%
12.	Type of Reporting Person (See Instructions)             PN

Page 2 of 11

CUSIP No. 368682100

1.	Names of Reporting Persons. QVT Financial GP LLC I.R.S. Identification Nos. of above persons (entities only).             11-3694007
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a)  ¨ (b)  x
3.	SEC Use Only
4.	Citizenship or Place of Organization             Delaware

Number of   Shares   Beneficially   Owned by   Each   Reporting   Person   With:	5.    Sole Voting Power                 0
	6.    Shared Voting Power                 3,635,024
	7.    Sole Dispositive Power                 0
	8.    Shared Dispositive Power                 3,635,024

9.	Aggregate Amount Beneficially Owned by Each Reporting Person             3,635,024
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)	¨
11.	Percent of Class Represented by Amount in Row (9)             6.38%
12.	Type of Reporting Person (See Instructions)             OO

Page 3 of 11

CUSIP No. 368682100

1.	Names of Reporting Persons. QVT Fund LP I.R.S. Identification Nos. of above persons (entities only).             98-0415217
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a)  ¨ (b)  x
3.	SEC Use Only
4.	Citizenship or Place of Organization             Cayman Islands

Number of   Shares   Beneficially   Owned by   Each   Reporting   Person   With:	5.    Sole Voting Power                 0
	6.    Shared Voting Power                 2,859,386
	7.    Sole Dispositive Power                 0
	8.    Shared Dispositive Power                 2,859,386

9.	Aggregate Amount Beneficially Owned by Each Reporting Person             2,859,386
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)	¨
11.	Percent of Class Represented by Amount in Row (9)             5.03%
12.	Type of Reporting Person (See Instructions)             PN

Page 4 of 11

CUSIP No. 368682100

1.	Names of Reporting Persons. QVT Associates GP LLC I.R.S. Identification Nos. of above persons (entities only).             01-0798253
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a)  ¨ (b)  x
3.	SEC Use Only
4.	Citizenship or Place of Organization             Delaware

Number of   Shares   Beneficially   Owned by   Each   Reporting   Person   With:	5.    Sole Voting Power                 0
	6.    Shared Voting Power                 3,173,781
	7.    Sole Dispositive Power                 0
	8.    Shared Dispositive Power                 3,173,781

9.	Aggregate Amount Beneficially Owned by Each Reporting Person             3,173,781
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)	¨
11.	Percent of Class Represented by Amount in Row (9)             5.58%
12.	Type of Reporting Person (See Instructions)             OO

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Item 1	(a).	Name of Issuer
		GenCorp Inc. (the “Issuer”)
Item 1	(b).	Address of Issuer’s Principal Executive Offices
		The address of the Issuer’s principal executive offices is:
		Highway 50 and Aerojet Road, Rancho Cordova, California 95742, United States
Item 2	(a).	Name of Person Filing
Item 2	(b).	Address of Principal Business Office or, if none, Residence
Item 2	(c).	Citizenship
		QVT Financial LP 1177 Avenue of the Americas, 9th Floor New York, New York 10036 Delaware Limited Partnership
		QVT Financial GP LLC 1177 Avenue of the Americas, 9th Floor New York, New York 10036 Delaware Limited Liability Company
		QVT Fund LP Walkers SPV, Walkers House Mary Street George Town, Grand Cayman KY1-9002, Cayman Islands Cayman Islands Limited Partnership
		QVT Associates GP LLC 1177 Avenue of the Americas, 9th Floor New York, New York 10036 Delaware Limited Liability Company
Item 2	(d).	Title of Class of Securities
		Common stock, $0.10 par value per share (the “Common Stock”).
Item 2	(e).	CUSIP Number
		The CUSIP number of the Common Stock is 368682100.
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
	(a)	¨	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).
	(b)	¨	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).
	(c)	¨	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

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	(d)	¨	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).
	(e)	¨	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
	(f)	¨	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
	(g)	¨	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
	(h)	¨	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
	(i)	¨	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
	(j)	¨	Group, in accordance with § 240.13d-1(b)(1)(ii)(J).
Item 4.	Ownership.
	(a)	Amount beneficially owned:
		QVT Financial LP (“QVT Financial”) is the investment manager for QVT Fund LP (the “Fund”), which beneficially owns 2,859,386 shares of Common Stock, consisting of 2,514,836 shares of Common Stock and an additional 344,550 shares of Common Stock issuable upon conversion of the Issuer’s convertible notes. QVT Financial is also the investment manager for Quintessence Fund L.P. (“Quintessence”), which beneficially owns 317,688 shares of Common Stock, consisting of 278,818 shares of Common Stock and an additional 38,850 shares of Common Stock issuable upon conversion of the Issuer’s convertible notes. In addition, QVT Financial is the investment manager for a separate discretionary account managed for Deutsche Bank AG (the “Separate Account”), which holds 461,243 shares of Common Stock, consisting of 384,643 shares of Common Stock and an additional 76,600 shares of Common Stock issuable upon conversion of the Issuer’s convertible notes. QVT Financial has the power to direct the vote and disposition of the Common Stock held by the Fund, Quintessence and the Separate Account. Accordingly, QVT Financial may be deemed to be the beneficial owner of an aggregate amount of 3,635,024 shares of Common Stock, consisting of the shares owned by, or underlying notes owned by, the Fund and Quintessence, and held in, or underlying notes held in, the Separate Account.
		QVT Financial GP LLC, as General Partner of QVT Financial, may be deemed to beneficially own the same number of shares of Common Stock reported by QVT Financial. QVT Associates GP LLC, as General Partner of the Fund and Quintessence, may be deemed to beneficially own the aggregate number of shares of Common Stock owned by the Fund and Quintessence, and accordingly, QVT Associates GP LLC may be deemed to be the beneficial owner of an aggregate amount of 3,173,781 shares of Common Stock.
		The Fund acquired beneficial ownership of more than 5% of the class of equity securities as of December 21, 2007. The reported share amounts reflect amounts beneficially owned by the reporting persons as of such date, as adjusted for subsequent transactions through the date hereof.
		Each of QVT Financial and QVT Financial GP LLC disclaims beneficial ownership of the shares of Common Stock owned by the Fund and Quintessence and held in the Separate

Page 7 of 11

		Account. QVT Associates GP LLC disclaims beneficial ownership of all shares of Common Stock owned by the Fund and Quintessence, except to the extent of its pecuniary interest therein.
		The percentage disclosed in Item 11 of the Cover Pages for each reporting person is calculated based upon the sum of (i) 56,500,000 shares of Common Stock outstanding, which is the total number of shares issued and outstanding as reported in the Issuer’s Quarterly Report on Form 10-Q for the quarter ended August 31, 2007, and (ii) the number of shares of Common Stock issuable upon conversion of the notes held by such reporting person.
	(b)	Percent of class:
		See Item 11 of the Cover Pages to this Schedule 13G.
	(c)	Number of shares as to which the person has:
		(i)	Sole power to vote or to direct the vote
			0
		(ii)	Shared power to vote or to direct the vote
			See item (a) above.
		(iii)	Sole power to dispose or to direct the disposition of
			0
		(iv)	Shared power to dispose or to direct the disposition of
			See item (a) above.
Item 5.	Ownership of Five Percent or Less of a Class
	If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following  ¨.
Item 6.	Ownership of More than Five Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company
	Not Applicable
Item 8.	Identification and Classification of Members of the Group
	Not Applicable
Item 9.	Notice of Dissolution of Group
	Not Applicable

Page 8 of 11

Item 10.	Certification
	By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

Page 9 of 11

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: December 28, 2007

QVT FINANCIAL LP		QVT FUND LP
By QVT Financial GP LLC,		By QVT Associates GP LLC,
its General Partner		its General Partner
By:	/s/ Daniel Gold	By:	/s/ Daniel Gold
Name:	Daniel Gold	Name:	Daniel Gold
Title:	Managing Member	Title:	Managing Member
By:	/s/ Lars Bader	By:	/s/ Lars Bader
Name:	Lars Bader	Name:	Lars Bader
Title:	Managing Member	Title:	Managing Member
QVT FINANCIAL GP LLC		QVT ASSOCIATES GP LLC
By:	/s/ Daniel Gold	By:	/s/ Daniel Gold
Name:	Daniel Gold	Name:	Daniel Gold
Title:	Managing Member	Title:	Managing Member
By:	/s/ Lars Bader	By:	/s/ Lars Bader
Name:	Lars Bader	Name:	Lars Bader
Title:	Managing Member	Title:	Managing Member

Page 10 of 11

EXHIBIT A

JOINT FILING AGREEMENT

The undersigned hereby agree that the statement on Schedule 13G signed by each of the undersigned shall be filed on behalf of each of the undersigned pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended.

Dated: December 28, 2007

QVT FINANCIAL LP		QVT FUND LP
By QVT Financial GP LLC,		By QVT Associates GP LLC,
its General Partner		its General Partner
By:	/s/ Daniel Gold	By:	/s/ Daniel Gold
Name:	Daniel Gold	Name:	Daniel Gold
Title:	Managing Member	Title:	Managing Member
By:	/s/ Lars Bader	By:	/s/ Lars Bader
Name:	Lars Bader	Name:	Lars Bader
Title:	Managing Member	Title:	Managing Member
QVT FINANCIAL GP LLC		QVT ASSOCIATES GP LLC
By:	/s/ Daniel Gold	By:	/s/ Daniel Gold
Name:	Daniel Gold	Name:	Daniel Gold
Title:	Managing Member	Title:	Managing Member
By:	/s/ Lars Bader	By:	/s/ Lars Bader
Name:	Lars Bader	Name:	Lars Bader
Title:	Managing Member	Title:	Managing Member

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