"Token unknown" for nonexistent colon

Hi!
I am using the Firebird managed data provider for .NET and Mono Version 1.6.3 with Firebird 1.5.1 and have a very strange problem.
I was able to open an FbConnection and could also write a tuple into my database:

FbTransaction t = Db.BeginTransaction();
string q = "insert into session(id, site) values(gen_id(sessionid,1),"+SiteId+")";
FbCommand command = new FbCommand(q, Db, t);
command.ExecuteNonQuery();
...

I am using the Marathon administration tool and a tuple was inserted correctly. So far so good...
Later in the program I tried to insert another tuple:

FbTransaction t = Db.BeginTransaction();
string q = "insert into screen(id, title) values(gen_id(screenid,1),'hello')";
FbCommand command = new FbCommand(q, Db, t);
command.ExecuteNonQuery();
...

But when the query is executed (last line before the "..."), a dynamic error occurs:

FirebirdSql.Data.Firebird.FbException: Dynamic SQL Error
SQL error code = -104
Token unknown - line 1, char 82
:

As far as I understand the message says that there is a misplaced colon at column 82 in the query string. But the string isn't even 82 characters long, apart from the fact that there is no colon in the string. I modified the string so that it was more than 82 characters long but, no matter what I wrote, the same error occurred. What can I do?

Thanks in advance for any help,
Christof

Yes... this was just too mysterious to be a Firebird bug. I found the mistake and it was not related to Firebird

That sounds very painful
Sounds like you have a problem yourself!
Glad you fixed it.