Hey Maslak,
Looking on Agilent's website you can see that the HP8594E was the replacement for the HP8594A. However, the user manual and information for the HP8594A is no longer available, because it is no longer supported by HP/Agilent.
If you can find the user manual for the 8594A then you can compare its functions to the 8594E. I would assume they would be very similar and it is very possible that the HP8594E driver will work. However, we do not have any documentation that says which functions won't work.
I hope this helps out.
JoshuaP
National Instruments