acl/src/main/java/org/springframework/security/acls/domain/AclImpl.java
@Override
	public void deleteAce(int aceIndex) throws NotFoundException {
		aclAuthorizationStrategy.securityCheck(this,
				AclAuthorizationStrategy.CHANGE_GENERAL);
		verifyAceIndexExists(aceIndex);

		synchronized (aces) {
			this.aces.remove(aceIndex);
		}
	}
@Override
	public void deleteAce(int aceIndex) throws NotFoundException {
		aclAuthorizationStrategy.securityCheck(this,
				AclAuthorizationStrategy.CHANGE_GENERAL);
		verifyAceIndexExists(aceIndex);

		synchronized (aces) {
			this.aces.remove(aceIndex);
		}
	}
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