Dual citizen with one passport?

Anyone have or know of a country that will put a stamp in a foreign countries passport showing that the person is also a citizen of that country?

Like lets say a dual citizen of the USA and Country X rather than carrying two passports just carries their USA passport which has a stamp in it from the government of Country X saying they are a citizen?

I was wondering about it because in Trinidad&Tobago the office that issues TT passports to citizens is…broken? Is that the word? Lets just say the requirements are crazy(but no worries if you know someone) and even if you satisfy them you need to wait years(my wife was told she would receive her passport in five years!). This article pretty much sums up the usual experience even though it is old:

http://www.newsday.co.tt/letters/0,73324.html

Anyway while spending time in the separate department that deals with foreigners from talking to fellow patrons it was revealed that a work around has been achieved where dual citizens are just bringing their Canadian or whatever passport and getting a stamp put in it certifying they are also a citizen of T&T rather than deal with the quagmire in the other department.

Any other countries do this?

New Zealand will- you can get either a stamp in your (foreign) passport or an electronic endorsement (that shows up on the immigration computer at the airport) which says “Even though Mr Smith is travelling on a foreign passport, he’s actually a New Zealand Citizen.”

I knew a guy who told me that he had a Bermuda stamp in his US passport that allowed him to live and work indefinitely in Bermuda, and that he got that stamp because his father was Bermudan. Not being really familiar with Bermudan nationality law, I’d guess that he was actually a Bermudan citizen and that this stamp may have been exactly what you are talking about.

I travel with a US passport and, for returning to Canada, a Canadian Citizenship ID card. I made the mistake of showing them both to an Air Canada agent in Barbados and she freaked, saying that that is not sufficient to enter Canada with. Of course, she was nuts. Now I will show only my US passport, since no visa is needed to enter Canada. Of course, the Canadian immigration officer wasn’t fazed in the least by this. It has never occurred to me to try get a special stamp from Canada in my passport. I imagine someone would have mentioned it to me if it were possible.