Mac doesn’t see LaCie d2 drives

[Bernhard Nessensohn]

also have a problem with lacie. have all my dates on it and suddenly today my mac (G5 with os10.4) could not read it anymore.
Also doesn’t work with another mac!
In diskutilities comes the following picture:

verifiy and repair disk “disk1s6”
checking HFS Plus volume.
invalid B-tree node size
volume check failed.

Error: the underlying task reported failure on exit

1HFS volume checked
1 volume could not be repaired because of an error

what can I do now?

[Bernhard Nessensohn]

I need some help with my lacie. It is not seen by my mac; what to do?