UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

___________________

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 2)*

Omega Navigation Enterprises, Inc.

(Name of Issuer)

Class A Common Stock

(Title of Class of Securities)

MHY6476R1053

(CUSIP Number)

April 20, 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:

	x	Rule 13d-1(b)
	o	Rule 13d-1(c)
	o	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 disclosures provided in a prior cover page.

The information required on 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 (the “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).

CUSIP No. MHY6476R1053

13G

Page 2 of 5 Pages

NAMES OF REPORTING PERSONS

PMA Capital Management Limited

CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions)

(a) o

(b) o

SEC USE ONLY

CITIZENSHIP OR PLACE OF ORGANIZATION

Cayman Islands

NUMBER OF

SHARES

BENEFICIALLY

OWNED BY

EACH

REPORTING

PERSON

WITH:

SOLE VOTING POWER

-0-

SHARED VOTING POWER

-0-

SOLE DISPOSITIVE POWER

-0-

SHARED DISPOSITIVE POWER

-0-

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

-0-

10.

CHECK IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES o

11.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)

0.00%

12.

TYPE OF REPORTING PERSON

CUSIP No. MHY6476R1053

Page 3 of 5 Pages

Item 1(a). Name of Issuer:

Omega Navigation Enterprises, Inc.

Item 1(b). Address of Issuer’s Principal Executive Offices:

24 Kaningos Street

Piraeus 185 34 Greece

Item 2(a). Names of Person Filing:

PMA Capital Management Limited

Item 2(b). Address of Principal Business Office or, if none, Residence:

Harbour Place, 103 South Church Street, P.O. Box 1034 GT, Grand Cayman, Cayman Islands

Item 2(c). Citizenship:

Cayman Islands

Item 2(d). Title of Class of Securities:

Class A Common Stock

Item 2(e). CUSIP Number:

MHY6476R1053

CUSIP No. MHY6476R1053

Page 4 of 5 Pages

Item 3.

If This Statement is Filed Pursuant to Rule 13d-1 (b), or 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 Exchange Act (15 U.S.C. 78c).

(c)

|_| Insurance company as defined in section 3(a)(19) of the Exchange Act (15 U.S.C. 78c).

(d)

|_| Investment company registered under section 8 of the Investment Company Act (15 U.S.C. 80a-8).

(e)

|X| 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 (15 U.S.C. 80a-3);

(j)

|_| Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Item 4. Ownership.

Incorporated by reference to Items 5-11 of the cover pages.

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 x.

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.

Item 10. Certifications.

CUSIP No. MHY6476R1053

Page 5 of 5 Pages

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and 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.

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.

Date: May 30, 2007

PMA CAPITAL MANAGEMENT LIMITED

By:		/s/ Kanwaljit S. Bahra
	Name:	Kanwaljit S. Bahra
	Title:	Authorized Signatory

PMA Capital Management LTD SC 13G/A