I've submited this clause directly to FireBird 1.5 Server and it works
fine:

SELECT * FROM Doc WHERE descr like '%inclusão%'

If I submit the same clause through a TIB_Query, setting it to query's
SQL property, i get this error:

EIB_ISCError with message ISC ERROR CODE:335544321
arithmetic exception, numeric overflow, or string truncation
Cannot transliterate character between charater sets

It seems that IBO 4_5_B doesn't support character '~' on a TIB_Query
SQL property. But, with portuguese language, it's often necessary to
use such characters.
Is there any way to resolve it?
Thanks,
Roberto