ok, let's clear things up.
there're only 4 possibilities:
1. Both parts are true => Entire statement is true. So the wife is an honestant and the husband is a swindlecant. PARADOX! Swindlecants don't tell the truth. So this is impossible.
2. First part is true, and second part is false => Entire statement is false. Wife is an honestant and husband is an honestant. PARADOX! Honestants always tell the truth. So this is also impossible.
3. First part is false, and second part is true => Entire statement is true. Wife is a swindlecant and husband is a swindlecant. PARADOX! Swindlecants always lie. So this is again impossible.
4. Both parts are false => Entire statement is true. Wife is a swindlecant and husband is an honestant. Only possible answer. Since the statement was given as an implication, the honestant is being tricky, but he isn't lying.
The thing about these truth/lie logic questions is that the background is usually that the inhabitants of the country while separated into these two distinct groups both love to try stumping the tourists with logic puzzles. So I don't see any inherent paradox in the honestant lying for both parts of the implication.
I have to disagree here. IF-THEN does not separate a statement into two independent phrases (that's what AND and OR do). IF-THEN makes one statement dependent on the other.
The solution is indeterminate:
For an Honestant to say "If my wife is an Honestant, then I am a Swindlecat" is a perfectly valid statement and indicates that there are no male Honestants with Honestant wives. It would be like me truthfully saying "If you are the king of Atlantis then I'm the Prince of the Moon!". I am not lying.
For a Swindlecat to say "If my wife is an Honestant, then I am a Swindlecat" is a perfectly valid statement also. It indicates that there are Honestants men who have married Honestant women, and others that have married Swindlecats, and that you can't tell that a husband is Swindlecat by knowing if his wife is or isn't. It is like my saying "If my wife has red hair, then I have brown". It is a lie because my wife's hair colour does not determine mine. It would only be impossible for me (a Swindlecat) to say this if there was some factor that meant that no redheaded women were married to brunettes. Or, as I just explained it to my brother, the statement "If you're name is Ian, then my name is Clive" is a lie (even though his name is Ian and mine is Clive). His name being Ian does not make my name Clive - my name could be John, or Barry. The IF-THEN relationship if false and makes the statement a lie.
Therefore, both an Honestant and a Swindlecat can make the statement and not break the rules. Without further information, we cannot tell which they are.
edit - oops, sorry for the double post - it was meant to be an edit, but I must have hit quote.