Firebird 1.5 RC 1

When i tried to do the backup today, i got this error:

gbak: ERROR: database file appears corrupt ()
gbak: ERROR: wrong page type
gbak: ERROR: page 42446 is of wrong type (expected 5, found 75)
gbak: ERROR: gds_$receive failed
gbak: Exiting before completion due to errors

After gfix -v -full

Summary of validation errors

Number of data page errors : 2
Number of index page errors : 5
Number of database page errors : 7

Ok, i have some page errors.

- What can be the cause of this?
- Is it normal to happen?
- After the recover process (i am following directives in ibphoenix
site), will i lose these two pages of data?
- This DB is stored in an encrypted device, and yesterday this
device gone full, with no more space left, causing some erros. Can
this be the cause?

Some entries in my log:

servidor.leonilda.com.br Thu May 1 10:50:30 2003
Database: tecelagem.gdb
Page 42446 wrong type (expected 5 encountered 75)

servidor.leonilda.com.br Thu May 1 10:53:00 2003
Database: tecelagem.gdb
Data page 42446 (sequence 725) is confused in table CAD1
(129)

servidor.leonilda.com.br Thu May 1 10:50:31 2003
Database: tecelagem.gdb
Index 5 is corrupt on page 81336 in table CTA2 (135)