§ 1448. Oath of renunciation and allegiance
(a) Public ceremony
A person who has applied for naturalization shall, in order to be and before being admitted to citizenship, take in a public ceremony before the Attorney General or a court with jurisdiction under section 1421 (b) of this title an oath
(1) to support the Constitution of the United States; >p>(2) to renounce and abjure absolutely and entirely all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty of whom or which the applicant was before a subject or citizen;
(3) to support and defend the Constitution and the laws of the United States against all enemies, foreign and domestic;
(4) to bear true faith and allegiance to the same; and
(5)
(A) to bear arms on behalf of the United States when required by the law, or
(B) to perform noncombatant service in the Armed Forces of the United States when required by the law, or
(C) to perform work of national importance under civilian direction when required by the law. Any such person shall be required to take an oath containing the substance of clauses (1) to (5) of the preceding sentence, except that a person who shows by clear and convincing evidence to the satisfaction of the Attorney General that he is opposed to the bearing of arms in the Armed Forces of the United States by reason of religious training and belief shall be required to take an oath containing the substance of clauses (1) to (4) and clauses (5)(B) and (5)(C) of this subsection, and a person who shows by clear and convincing evidence to the satisfaction of the Attorney General that he is opposed to any type of service in the Armed Forces of the United States by reason of religious training and belief shall be required to take an oath containing the substance of said clauses (1) to (4) and clause (5)(C). The term religious training and belief as used in this section shall mean an individuals belief in a relation to a Supreme Being involving duties superior to those arising from any human relation, but does not include essentially political, sociological, or philosophical views or a merely personal moral code. In the case of the naturalization of a child under the provisions of section 1433 of this title the Attorney General may waive the taking of the oath if in the opinion of the Attorney General the child is unable to understand its meaning. The Attorney General may waive the taking of the oath by a person if in the opinion of the Attorney General the person is unable to understand, or to communicate an understanding of, its meaning because of a physical or developmental disability or mental impairment. If the Attorney General waives the taking of the oath by a person under the preceding sentence, the person shall be considered to have met the requirements of section 1427 (a)(3) of this title with respect to attachment to the principles of the Constitution and well disposition to the good order and happiness of the United States.
http://www.law.cornell.edu/uscode/html/uscode08/usc_sec_08_00001448----000-.html
I did. But, you'll note that there is no legal requirement that you give up other citizenships, just your allegiance to those countries.
Congress allows dual citizenship.