Boolean property based search scopes - FAST Search

In my SharePoint list I have a column of type Yes/No. The requirement is to create the scope based on this column. It was quite easy when you have the SharePoint 2010 search. But once I move to FAST Search, this scope was not working.

I followed all steps as suggested in technet for creation of scope.
1. Create the managed property of type boolean on (FAST Search Server)
2. Map the crawled property to above managed property
3. Run Full crawl
4. Create the managed property of boolean type on Server schema with the same name as in step 1.
5. Create the scope based on the property rule i.e. propertyname = TRUE

However this doesn't work. Glad to find out the workaround or trick for this problem.

You should create the Server schema managed property of type TEXT instead of Boolean. Now your scope works.

When you create the scope with the boolean type property and pass TRUE or YES value it get converted to 1. Similarly for FALSE or NO it will be 0. For example:- propertyname = TRUE is convered to propertyname = 1. When you use this scope the FAST query server fails to treat 1 as TRUE and hence you won't get any results.

Instead if you create the scope with text type properyname then the scope rule will be saved as propertyname = TRUE.  Now the FAST query server treats correctly and hence you get results.