Replace "unknown token" by specific messages.

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59526 65644016-39b1-43b1-bf79-96bc8fe82c15
nightly update

git-svn-id: svn+ssh://svn.code.sf.net/p/firebird/code/firebird/trunk@59527 65644016-39b1-43b1-bf79-96bc8fe82c15