Can't delete table in Firebird

I'll open a command prompt in Ubuntu

and then enter in Firebird

, for example:

$ isql-fb
SQL> connect "localhost:/var/lib/firebird/2.5/data/reestr.fdb" user 'SYSDBA' password 'root';

      

        
        
        
      

    

Then I list all tables in my database:

 > show tables;
   ARCHIVE_1_    ...
   ...
   ...

      

        
        
        
      

    

Finally, I want to drop one table. I try like this:

> DROP TABLE ARCHIVE_1_;
........ absolutely no reaction, propmt is waiting for something

      

        
        
        
      

    

If I log in again and list the tables, I see that the table still exists. So what's wrong with all of this?

EDIT

This is what the command returns set;

at the isql prompt:

Print statistics:        OFF
Echo commands:           OFF
List format:             OFF
List Row Count:          OFF
Select rowcount limit:   0
Autocommit DDL:          ON
Access Plan:             OFF
Access Plan only:        OFF
Display BLOB type:       1
Column headings:         ON
Terminator:              ;
Time:                    OFF
Warnings:                ON
Bail on error:           OFF