Proxy for object in a background process

I want to use ruby-ldap in my application, but it appears that the
underlying library’s use of native IO causes my Ruby threads to block
waiting for the LDAP server’s response (correct me if I’m wrong there).
Since the application is doing other networking and GUI stuff at the
same time, I’d like to avoid this delay.

In looking for a solution, I saw ‘detach’ and ‘slave’ in the RAA, but
both use fork() to do their stuff. While Linux is my primary platform,
it would be neat if my app could run on Win32 as well.

Does anyone have experience solving this problem in a portable way?

thanks!
dave