How far away is a challenge to the federal DOMA?

A judge has ruled that gay and lesbian residents of Rhode Island are allowed to marry in Massachusetts because the latter's law that such marriages can only take place when they are not considered illegal in the applicants' state of residence doesn't apply to the smallest state in the nation, since no such limitations exist:

A Boston judge has ruled that a Massachusetts law forbidding out-of-state residents from marrying in Massachusetts if their marriage would not be permitted in their home state does not apply to Rhode Island.

Superior Court Judge Thomas Connolly said that Rhode Island does not specifically ban gay marriage.
[...]
"No evidence was introduced before this court of a constitutional amendment, statute, or controlling appellate decision from Rhode Island that explicitly deems void or otherwise expressly forbids same-sex marriage," he ruled.

And it looks like the ruling won't be appealed:

Attorney General Thomas Reilly said he would not appeal. Reilly, a Democrat, is running for governor.

And once a couple from Rhode Island has married, they can file federal taxes as married. After that, their filing would be rejected because of the DOMA, and they could sue the federal government because the Constitution states that whatever "contract" is recognized by one state, has to be recognized by all others.

And marriage is a contract.

Let's just hope Bush doesn't get a chance to appoint another right wingnut to the Supreme Court before such a challenge reaches it.