I'm just about to try out the NXClient to connect with my school's citrix server....I'll post my results here once I've attempted.
I did try installing the citrix client on my Zaurus, but it gave me some esoteric complaint which I can't reproduce from memory.
I'm running OZ3.36-pre1 with opie 1.14 using the hentges mods/ROM
I can run the NXClient using the compat libs fine...as I say, I'll report back findings here.