I used to work on an old AIX box that made dbms that way. And for the life of me I can't remember what format they are. I can tell you what they aren't. They're aren't Berkeley or GNU. If you can get them on a Linux box, you can run "file whatever" and it can tell you what they are. There may also be some way of getting perl to tell you the compile time options it has, because the default DBM library is system dependant.

Hope this helps...

/\/\averick