kiwiFrog - 2008-11-24

Hi, I'm getting the following exception when trying to open a .db file.
The file starts like this :

"
¬í w HTREE   sr java.math.BigIntegerŒüŸ©;û I bitCountI     bitLengthI firstNonzeroByteNumI
"

Is this an incorrect format for a JDBM database file??
Thanks in advance for your help,
Cheers,