How do I identify and resolve the cause of Firebird Abnormal Termination (4294967295)?

We produce an accounting system and we are presently migrating our system across to Firebird 1.54 from Interbase 5.6.  We have found that at some sites on an irregular basis we get the following error in the firebird event log.  We have now installed a debug version of firebird installed at one of the sites experiencing the problem (around 10 incidents over a 4 week period).

SERVER1 (Client)          Fri Nov 23 14:27:50 2007
C:\Program Files\Firebird\Firebird_1_5\bin\fbserver.exe: terminated abnormally (4294967295)

NOTE: The value of 4294967295 (0xFFFFFFFF) reported in the log file could perhaps be interrupted as -1 for a 32 bit signed INT if that has more meaning for this problem.  

In the windows event log the following messages appear:
The description for Event ID ( 281 ) in Source ( FirebirdGuardianDefaultInstance ) cannot be found. The local computer may not have the necessary registry information or message DLL files to display messages from a remote computer. You may be able to use the /AUXSOURCE= flag to retrieve this description; see Help and Support for details. The following information is part of the event: Abnormal Termination: C:\Program Files\Firebird\Firebird_1_5\bin\fbserver.exe: terminated abnormally (4294967295).
 
The servers on which Firebird run are dedicated IBM Windows 2003 Servers, configured with RAID 5, 3.x ghz processor with typically 4 Gig of Memmory installed.  The method of connection to the database is by the BDE which we are getting ready to replace and we have a number of applications that access the database.  The firebird debug version of firebird has been installed at one of the sites (Firebird-1.5.4.4910-0-Win32_pdb.exe) and a Crash Dump file has been generated for one of the abnormal terminations.  This file can be made available if it is of use.