problem getting arguments for perform:withArguments:

I am trying to get information out of an island using signal:withArguments: to
an outside object waiting with perform:withArguments:

More precisely I have a tObject with a tFarRef and some outside object,  obj.

I do

obj runScript: #selector when: {tFarRef . #msg}.

and then have a perform:withArguments: method for obj.

Later tObject is called with:

self signal: #msg withArguments: #('1234').

obj's perform:withArguments: method gets called with #selector, but
withArguments gets #().

The doc seems to say this is the only way to get info out of an island, but
it's not getting any info out. How do I get information from tObject to obj?

Thanks,

Matthew