http://www.freetds.org/userguide/freetdsconf.htm
But ultimately this too is a core setting in SQL Server. See the SET TEXTSIZE documentation and things like dbcc user options. TinyTDS should not get in the way of these settings. We even have a few tests too. Things are kind of murky when there is no freetds.conf in scope, the default should be controlled by SQL Server at that point. Let me know what you find out.
- Ken