Is this correct about incompatibility???

> > IBAdmin tab is empty if it the loaded gds32.dll is not 6.0 or higher.
>
> You're right, I've just installed Firebird 1.5
>

IBX is not tested with nor designed to work with Firebird.

> The changes are :
> 2 dll instead of the gds32.dll
> - gds32.dll (32 Ko - for compatibility)
> - fbclient.dll (400 Ko)
>
> What can I do to solve this problem ?

Go to the correct InterBase Dll.

> Do you want I mail you 'gds32.dll FB1.5' for your analyse
> to let 'IB Admin tab' avaible with this last one ?

if FB wants it compatible then they are responsible to stay compatible.

IBX is designed to work with InterBase and the InterBase OE only.