I installed Firebird 1.5.2 from an rpm onto a mandrake 10.1 system.
A number of issues prevent me from using the database:
1. It has set up a user account called Firebird but I have no idea
what the password for that account is the mask shows 5 chars though
2. gsec, isql etc just do not work. I get a command missing message
when I try gsec -user sysdba -password masterkey. I have logged in
as root. I notice the bin directory has gsec*, isql* etc, what does
this mean. (figured it out boy do I feel stupid).
3. I tried usermod -G Firebird myusername but that doesnt seem to
have made any difference, oops actually it did.
4. Having figured out 1 I try gsec user etc again... no dice.

You know what anyone else who is a complete Newb like me I can save
you having to embarass yourselves...by actually posting this.

Remember to type ./gsec , ./isql etc.. Get root privileges to read
the SYSDBA.password file. Follow the directions.

Good Luck ;)